Friends

Cat Birthday Party & Tree House

A cozy little pet set that punches above its size

Brick Rated Score

3.8/5

Set 42666 · 2025

Pieces321

Minifigsn/a

Year2025

Set number42666

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The verdict

I like that Friends keeps making sets like this, small enough for a weekend afternoon build, cheerful enough that a cat-loving kid or adult won't outgrow it in a week. It is not going to wow a serious display builder, there is no clever new technique hiding in here, but it does exactly what it promises. If you or your kid is into cats and small cozy builds, it earns its spot on a shelf.

Best for: Cat lovers and younger Friends fans who want a quick, cheerful weekend build

The full review

What it is

This one caught me off guard because it looks like a simple pet playset in the box shot, but once it's built you've got a genuine two-scene set, a tree house and a party spread, packed into a modest piece count. There's a nice sense that the designers gave the cat a whole little world, a spot to climb, a spot to celebrate, rather than just bolting a cat minifig accessory onto a generic building.

The catch

I'll be honest about where the caveats sit. At 321 pieces this is not a set that keeps your hands busy for hours, and it is not chasing the kind of engineering cleverness that gets written up on fan blogs. The parts skew toward simple, chunky shapes built for a younger audience, so if you're the kind of builder who wants a new part usage or a tricky technique to talk about, you won't find much of that here.

Who it's for

I'd point this at a parent building with a cat-obsessed kid, or a Friends completist who likes rounding out their pet-themed shelf. If you're after a serious display piece or an adult-focused build session, this is one to skip in favor of one of the larger Friends sets in the same wave.

The parts story

What the build is actually like, and the pieces worth knowing about.

The build itself moves fast and in clear stages, first the tree house structure, then the party furniture and accessories, so you get a satisfying sense of progress every few minutes rather than a long slog through one repetitive section. It's the kind of pacing that works well if you're building alongside a younger kid who wants to see results quickly.

Nothing in here is going to make the parts-hunting crowd sit up, the value is really in the cheerful little accessories, party props, tree house fittings, and the cat itself, that make the finished scene feel lived in rather than the piece count alone. It's a set that spends its budget on personality rather than rare elements.

Fun facts

01The set pairs two builds in one box, a tree house and a birthday party scene, giving it more play value than its piece count alone suggests.
02It's part of LEGO Friends' ongoing push into pet-focused sets, following the theme's long-running interest in animal companions for its cast of characters.
03At 321 pieces, it sits comfortably in the smaller end of the Friends lineup, positioned as an easy entry point build rather than a flagship set.