# LEGO 42666-1 — Cat Birthday Party & Tree House (2025)

Source: https://www.brickmissing.com/sets/42666-1-cat-birthday-party-tree-house
Publisher: BrickMissing (https://www.brickmissing.com) — free LEGO parts checker. Not affiliated with the LEGO Group.

The LEGO Friends 42666 Cat Birthday Party & Tree House invites you to a festive celebration in Heartlake City. This 321-piece set brings LEGO Friends characters Leo and Paisley together with Churro, the birthday cat, and four additional feline friends for a grand event. Explore the multi-level cat tree house, complete with a fish-shaped piñata, a refreshing water fountain, cat grass, and a hidden litter box. Adorned with colorful birthday banners, presents, and cheerful cat-shaped balloons, the scene culminates around a rotating table where Churro’s special birthday cake awaits. This vibrant model offers many detailed components, from the intricate piñata design to the functional rotating dining area, ensuring a lively display.

## Set facts

- Set number: 42666-1
- Name: Cat Birthday Party & Tree House
- Theme: Friends › Pets
- Released: 2025
- Pieces: 321
- Distinct part + colour lots: 146
- LEGO retail price: € 29,99
- Build difficulty: intermediate
- Repairability: 6.2% of this set's lots are hard to replace (9 of 146 part+colour combinations appear in three or fewer sets in the entire LEGO catalog).

## Complete parts list (146 lots, 321 pieces)

Prices are the official LEGO Pick a Brick price per individual part, where LEGO publishes one.

| Qty | Part | Colour | Part no. | LEGO element ID | LEGO price each |
| ---: | --- | --- | --- | --- | --- |
| 1 | Sticker Sheet for Set 42666-1 | Unknown | 10113040 | 6542237 | — |
| 2 | Bar Holder with Clip | White | 11090 | 6341465 | €0,12 |
| 1 | Plate Special 1 x 2 with Clip Horizontal on Side | White | 11476 | 6313115 | €0,15 |
| 2 | Slope Curved 2 x 1 No Studs [1/2 Bow] | Bright Green | 11477 | 6460836 | €0,06 |
| 1 | Animal, Cat, Sitting with Dark Brown Stripes, White Chest, Ears print | Medium Brown | 11602pr0010 | 6520143 | €2,17 |
| 1 | Headwear Accessory Bow with Heart, Long Ribbon and Pin | Lavender | 11618 | 6023826 | €0,08 |
| 1 | String with End Studs 11L Overall | Black | 14226c11 | 6096955 | €1,96 |
| 2 | Brick Arch 1 x 5 x 4 [Continuous Bow, Raised Underside Cross Supports] | Tan | 14395 | 6075057 | €0,28 |
| 1 | Brick Arch 1 x 6 x 2 - Thin Top without Reinforced Underside [New Version] | Medium Azure | 15254 | 6059179 | €0,27 |
| 2 | Brick Round 2 x 2 Dome Bottom [Open Stud] | Bright Pink | 15395 | 6541655 | €0,17 |
| 1 | Plate Round 1 x 2 Half Circle with Stud (Jumper) | Black | 1745 | 6533009 | €0,15 |
| 2 | Tile Round 1 x 2 Half Circle | Medium Azure | 1748 | 6510074 | €0,13 |
| 2 | Brick Arch 1 x 3 x 2 Inverted [Inside Bow] | Medium Azure | 18653 | 6357619 | €0,16 |
| 4 | Plate Special Round 2 x 2 with Center Stud (Jumper Plate) | Dark Pink | 18674 | 6223767 | €0,07 |
| 2 | Plate Special Round 2 x 2 with Center Stud (Jumper Plate) | Black | 18674 | 6194417 | €0,07 |
| 3 | Plate Special Round 2 x 2 with Center Stud (Jumper Plate) | Bright Green | 18674 | 6380676 | €0,07 |
| 1 | Plant, Flower with 5 Pointed Petals and Pin | Light Aqua | 18853 | 6500671 | €0,06 |
| 1 | Brick Special 1 x 2 x 1 2/3 with 4 Studs on 1 Side | Red | 22885 | 6513765 | €0,17 |
| 1 | Bar Holder with Hole and Bar Handle | Reddish Brown | 23443 | 6476174 | €0,07 |
| 2 | Large Figure Weapon Lightsaber Hilt with Axle Hole and Two Bar Holders | Reddish Brown | 24122 | 6459423 | €0,17 |
| 1 | Headwear Accessory Hat with Small Pin, Clown / Party with Pin | Pearl Gold | 24131 | 6287612 | €0,17 |
| 8 | Plant, Leaves 4 x 3 | Lime | 2423 | 6268818 | €0,15 |
| 2 | Tile 1 x 4 with Groove | Bright Green | 2431 | 6195267 | €0,12 |
| 2 | Plant, Flower, Plate Round 1 x 1 with 5 Petals | Lavender | 24866 | 6214235 | €0,06 |
| 4 | Plant, Flower, Plate Round 1 x 1 with 5 Petals | Bright Green | 24866 | 6206150 | €0,06 |
| 2 | Plant, Flower, Plate Round 1 x 1 with 5 Petals | Bright Light Yellow | 24866 | 6426463 | €0,06 |
| 6 | Brick Round 1 x 1 diameter Tube with 90 Degree Elbow (2 x 2 x 1) and Axle Holes (Crossholes) at each end | Tan | 25214 | 6541476 | €0,23 |
| 1 | Animal, Cat, Chubby with orange Face, Toes, Medium Blue/Lime Eyes print | White | 2652pr0003 | 6520273 | €2,47 |
| 1 | Animal, Cat, Chubby with Bright Green Eyes, Light Bluish Grey Fur print | Dark Bluish Gray | 2652pr0007 | 6542233 | €2,47 |
| 2 | Tile 2 x 3 | Black | 26603 | 6196596 | €0,11 |
| 1 | Turntable 2 x 2 Female | White | 27448 | 6536567 | €0,12 |
| 2 | Tile 2 x 2 Curved, Macaroni | Coral | 27925 | 6250024 | €0,08 |
| 1 | Container Box 2 x 2 x 1 Reinforced Bottom | Bright Light Orange | 2821 | 6439231 | €0,29 |
| 3 | Container Box 2 x 2 x 1 Reinforced Bottom | Bright Pink | 2821 | 6517936 | €0,29 |
| 3 | Brick Special 1 x 2 with Grille | Tan | 2877 | 4655900 | €0,16 |
| 1 | Brick 2 x 3 | Dark Orange | 3002 | 6536259 | €0,17 |
| 3 | Brick 1 x 2 | Bright Light Orange | 3004 | 6003003 | €0,11 |
| 3 | Brick 1 x 2 | Coral | 3004 | 6258572 | €0,11 |
| 3 | Brick 1 x 2 | Dark Orange | 3004 | 4579659 | €0,11 |
| 5 | Brick 1 x 1 | Medium Azure | 3005 | 4619652 | €0,07 |
| 3 | Brick 1 x 1 | Coral | 3005 | 6422915 | €0,07 |
| 3 | Brick 1 x 1 | Bright Light Orange | 3005 | 6061685 | €0,07 |
| 2 | Brick 1 x 4 | Medium Azure | 3010 | 6036238 | €0,16 |
| 1 | Plate 2 x 4 | Medium Lavender | 3020 | 4619516 | €0,15 |
| 2 | Plate 2 x 4 | Orange | 3020 | 4158355 | €0,15 |
| 1 | Plate 2 x 3 | Light Aqua | 3021 | 6426724 | €0,13 |
| 1 | Plate 2 x 2 | Light Bluish Gray | 3022 | 4211397 | €0,10 |
| 5 | Plate 1 x 2 | Dark Orange | 3023 | 4570877 | €0,08 |
| 2 | Plate 6 x 10 | Lime | 3033 | 6289699 | €0,71 |
| 2 | Bar 4L (Lightsaber Blade / Wand) | White | 30374 | 6116602 | €0,05 |
| 1 | Tile 2 x 2 with Groove | Bright Light Orange | 3068b | 6020147 | €0,07 |
| 2 | Tile 2 x 2 with Groove | Bright Pink | 3068b | 4615728 | €0,07 |
| 4 | Tile 1 x 2 with Groove | Medium Azure | 3069b | 4649741 | €0,07 |
| 2 | Tile 1 x 2 with Groove | Red | 3069b | 6213779 | €0,07 |
| 2 | Tile 1 x 2 with Cat Food Box, Cat, White 'MEOW BITS' print | Light Aqua | 3069bpr9932 | 6527761 | €0,25 |
| 3 | Plate Special 1 x 2 with Door Rail | Tan | 32028 | 4160483 | €0,05 |
| 6 | Technic Axle 2 Notched | Red | 32062 | 4142865 | €0,07 |
| 25 | Plant, Plate 1 x 1 Round with 3 Leaves | Yellowish Green | 32607 | 6541652 | €0,06 |
| 4 | Plant, Plate 1 x 1 Round with 3 Leaves | Bright Green | 32607 | 6182261 | €0,06 |
| 2 | Slope Curved 2 x 2 x 2/3 Inverted | Bright Light Blue | 32803 | 6336860 | €0,11 |
| 1 | Plate Round 1 x 1 with Hollow Stud and Horizontal Bar 1L | Black | 32828 | 6196548 | €0,05 |
| 1 | Slope 33° 3 x 2 | Reddish Brown | 3298 | 4216625 | €0,12 |
| 1 | Headwear Accessory Crown / Tiara | Pearl Gold | 33322 | 6173109 | €0,10 |
| 2 | Bar 1L with Clip [Cut Edges and One Side Hole] [Full Clip] | Reddish Brown | 3484 | 6439053 | €0,07 |
| 1 | Plate Special 4 x 4 with 3 x 3 Quarter Round Cutout | Bright Pink | 35044 | 6526012 | €0,22 |
| 1 | Plate Special 4 x 4 with 3 x 3 Quarter Round Cutout | Yellow | 35044 | 6474986 | €0,22 |
| 1 | Plate Special 1 x 2 Rounded with 2 Open Studs | Tan | 35480 | 6212758 | €0,07 |
| 2 | Plate Special 1 x 2 Rounded with 2 Open Studs | Bright Green | 35480 | 6536987 | €0,07 |
| 2 | Brick 1 x 3 | White | 3622 | 362201 | €0,15 |
| 1 | Brick Arch 1 x 4 | Bright Light Orange | 3659 | 6071607 | €0,16 |
| 1 | Technic Brick 1 x 2 [1 Pin Hole] | Reddish Brown | 3700 | 4211252 | €0,12 |
| 2 | Plate 1 x 4 | Bright Green | 3710 | 6395814 | €0,12 |
| 2 | Brick Curved 1 x 2 x 1 No Studs | Tan | 37352 | 6391523 | €0,11 |
| 6 | Plant, Stem with 3 Leaves and Bottom Pin | Bright Green | 37695 | 6235080 | €0,13 |
| 6 | Equipment Candlestick | Reddish Brown | 37762 | 6422088 | €0,07 |
| 1 | Equipment Candlestick | Black | 37762 | 6290456 | €0,07 |
| 1 | Wave / Flame Small with Pin | Trans-Orange | 37775 | 6357747 | €0,10 |
| 1 | Equipment Shovel [Rounded Handle End] | Flat Silver | 3837 | 6210601 | €0,13 |
| 1 | Antenna 1 x 4 with Flat Top | Dark Orange | 3957b | 6514016 | €0,06 |
| 3 | Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) | Bright Pink | 4032a | 6498749 | €0,06 |
| 2 | Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) | Medium Azure | 4032a | 6109752 | €0,06 |
| 1 | Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) | Medium Nougat | 4032a | 6167643 | €0,06 |
| 2 | Brick Special 1 x 1 with Headlight | Bright Light Blue | 4070 | 6387434 | €0,07 |
| 1 | Plate 8 x 8 with Rounded End | Magenta | 41948 | 6349472 | €0,93 |
| 1 | Technic Pin 1/2 | Light Bluish Gray | 4274 | 4211483 | €0,05 |
| 3 | Plate 1 x 10 | Medium Azure | 4477 | 6423273 | €0,16 |
| 2 | Dish 2 x 2 Inverted [Radar] | Black | 4740 | 4570283 | €0,05 |
| 1 | Dish 2 x 2 Inverted [Radar] | Trans-Light Blue | 4740 | 6245307 | €0,10 |
| 1 | Brick Special 1 x 1 with Studs on 2 Sides | Black | 47905 | 6531923 | €0,11 |
| 2 | Plant, Leaves Stacked 4 x 5 x 1 2/3 | Bright Green | 5058 | 6507837 | €0,57 |
| 3 | Plant, Leaves Stacked 4 x 5 x 1 2/3 | Lime | 5058 | 6522798 | €0,57 |
| 1 | Wedge Plate 2 x 4 | Black | 51739 | 4609454 | €0,10 |
| 1 | Plate Round 1 x 1 Swirled Top / Poo | Reddish Brown | 53119 | 6438899 | €0,08 |
| 4 | Animal Body Part, Barb / Claw / Tooth / Talon / Horn, Small | Bright Green | 53451 | 6527826 | €0,07 |
| 2 | Slope 30° 1 x 1 x 2/3 (Cheese Slope) | Bright Light Blue | 54200 | 6372124 | €0,06 |
| 2 | Brick Round 2 x 2 Dome Top with 2 Ears | Bright Pink | 5690 | 6483520 | — |
| 3 | Technic Axle Connector Hub with 3 Axles at 120° | Light Bluish Gray | 57585 | 4502595 | €0,28 |
| 2 | Plant, Flower, Peony Rose with 2 Layers | Medium Lavender | 5904 | 6550818 | €0,10 |
| 6 | Technic Axle Connector Smooth [with x Hole + Orientation] | Tan | 59443 | 6262188 | €0,06 |
| 1 | Cone 1 x 1 [Top Groove] | Trans-Light Blue | 59900 | 6514027 | €0,08 |
| 6 | Cone 1 x 1 [Top Groove] | Tan | 59900 | 4529237 | €0,05 |
| 1 | Plate Round Corner 6 x 6 | Lime | 6003 | 6129601 | €0,59 |
| 2 | Plate Round Corner 6 x 6 | Black | 6003 | 6093691 | €0,51 |
| 1 | Window 1 x 4 x 3 without Shutter Tabs | White | 60594 | 4530590 | €0,23 |
| 4 | Plate Round 1 x 1 with Solid Stud | Bright Pink | 6141 | 4517996 | €0,05 |
| 1 | Plate Round 1 x 1 with Solid Stud | Trans-Light Blue | 6141 | 6514058 | €0,05 |
| 1 | Brick Arch 1 x 4 x 2 | Coral | 6182 | 6519696 | €0,28 |
| 3 | Cylinder Half 2 x 4 x 4 | Tan | 6259 | 6232142 | €0,62 |
| 1 | Animal, Fish [Hollow Stud Mouth] | Bright Light Blue | 64648 | 6195347 | €0,12 |
| 4 | Plate Special 2 x 4 with Groove and Two Center Studs (Jumper) | Bright Green | 65509 | 6293826 | €0,18 |
| 1 | Wool / Yarn | Dark Pink | 6900 | 6509764 | €0,53 |
| 1 | Wool / Yarn | Bright Light Yellow | 6900 | 6522800 | €0,53 |
| 1 | Headwear Accessory Hat with Small Pin, Cap | Lime | 6913 | 6509777 | €0,29 |
| 1 | Animal, Cat, Kitten Sitting with Open Eyes, White Mouth, Nougat Paws print | Nougat | 69902pr0003 | 6542234 | €1,92 |
| 1 | Animal, Cat, Kitten Sitting with Yellow Eyes, Dark Pink Tongue print | Black | 69902pr0004 | 6520727 | €1,92 |
| 1 | Plate Special 2 x 2 x 2/3 with Axle Hole and Grill on Sides (Haybale) | Tan | 71752 | 6330903 | €0,40 |
| 1 | Hose Rigid 3mm D. 9L / 7.2cm | Black | 75c09 | 6409912 | €0,76 |
| 1 | Plate Special 1 x 2 with Clip Vertical on End | Reddish Brown | 78256 | 6459597 | €0,19 |
| 1 | Bar 2L with Stop in Center | White | 78258 | 6357680 | €0,10 |
| 4 | Bar 2L with Stop in Center | Tan | 78258 | 6447501 | €0,10 |
| 2 | Bar 2L with Stop in Center | Reddish Brown | 78258 | 6451002 | €0,10 |
| 2 | Brick Curved 2 x 1 with Inverted Cutout | Bright Light Orange | 78666 | 6392166 | €0,10 |
| 2 | Brick Curved 2 x 1 with Inverted Cutout | Coral | 78666 | 6541654 | €0,10 |
| 3 | Flag 2 x 2 Square, Flared Clip Edge [Thick Clips] | White | 80326 | 6365487 | €0,24 |
| 1 | Brick Special 1 x 2 with 1 Center Stud on 1 Side, Bottom Stud Holder | Bright Light Blue | 86876 | 6522315 | €0,15 |
| 1 | Plate 1 x 1 x 2/3 with Open Stud | Dark Orange | 86996 | 6382577 | €0,08 |
| 1 | Brick Round 4 x 4 Centre Hole | Yellow | 87081 | 6490950 | €0,36 |
| 2 | Panel 1 x 2 x 3 [Side Supports / Hollow Studs] | White | 87544 | 4585448 | €0,17 |
| 1 | Plate Special 2 x 2 with Groove and Center Stud (Jumper) | Bright Pink | 87580 | 6251842 | €0,07 |
| 5 | Plate Special 2 x 2 with Groove and Center Stud (Jumper) | Medium Azure | 87580 | 6126090 | €0,07 |
| 1 | Plate Special 2 x 2 with Groove and Center Stud (Jumper) | Yellow | 87580 | 6126050 | €0,07 |
| 1 | Bar 5L with Handle (Friction Ram) | Black | 87618 | 4623113 | €0,18 |
| 4 | Plate Special 1 x 2 with Bar Up [Horizontal Arm 5mm] | Tan | 88072 | 6261357 | €0,18 |
| 2 | Plate Special 1 x 2 with Bar Up [Horizontal Arm 5mm] | Light Bluish Gray | 88072 | 6261358 | €0,18 |
| 1 | Cupboard 2 x 3 x 2 with Hollow Studs | Black | 92410 | 6313992 | €0,36 |
| 1 | Tile Round 1 x 1 | Trans-Yellow | 98138 | 6274740 | €0,05 |
| 2 | Tile Round 1 x 1 with Offset Black Eye Print | White | 98138pr0008 | 6284599 | €0,13 |
| 6 | Tile Round 1 x 1 with Animal Track Print | Medium Nougat | 98138pr0056 | 6287856 | €0,13 |
| 1 | Minidoll Head Thick Black Eyebrows, Reddish Brown Eyes, Smile print | Medium Nougat | 92198pr0335 | 6416551 | €0,57 |
| 1 | Minidoll Torso Boy with Medium Nougat Arms and Hands with Magenta/Coral Jacket, Medium Blue Trim, White Shirt, Orange/Azure Shapes print | Medium Nougat | 11408c02pr0013 | 6541122 | — |
| 1 | Hair Scruffy and Swept Right | Reddish Brown | 40938 | 6424457 | €0,29 |
| 1 | Minidoll Hips and Cargo Pants with Nougat Legs, Medium Azure/White Shoes print [Thin Hinge] | Yellow | 2268c01pr0006 | 6430246 | €2,66 |
| 1 | Hair, Long Wavy Across Face | Dark Red | 2645 | 6409769 | €0,39 |
| 1 | Minidoll Head Dark Red Eyebrows, Medium Azure Eyes, Nougat Lips print | Light Nougat | 92198pr0346 | 6416490 | €0,57 |
| 1 | Minidoll Torso Girl with Bright Light Yellow Top, Coral/Dark Blue Shapes, Writing, Lavender Shirt print, Light Nougat Arms and Hands | Light Nougat | 92456c01pr0035 | 6469304 | €2,99 |
| 1 | Minidoll Hips and Shorts with Warm Tan Legs, Dark Tan Shoes, White Laces, Socks, Laces | Medium Lavender | 36198c01pr0004 | 6484627 | €2,66 |

## Notes

- Track which of these parts you own and see what is missing: https://www.brickmissing.com/sets/42666-1-cat-birthday-party-tree-house
- Inventory data is based on official LEGO inventories via the Rebrickable catalog, updated daily.
- Part images, minifigure lists and related sets are on the set page: https://www.brickmissing.com/sets/42666-1-cat-birthday-party-tree-house