I've worked with lots of kids and the one thing I've never thought as a child gleefully threw sand at my face and then wiped their entire face on their shirt was "damn, I wish that kid was wearing Stella McCartney right now." Don't get me wrong, kids look adorable in tuxedos and party gowns, but I don't know if they should be the target demographic for beautiful and expensive clothes that they could stain, rip, or somehow burn off themselves at any time.
Borrow Mini Couture has other ideas. The company functions much like rental companies for adult clothes would. Parents get to browse an amazing selection of high-end clothes for their children, which they can then rent for up to five days for a fraction of the price that buying (and inevitably ruing) would entail. Stella McCartney is one of the designers available and optimistic parents can rent a dress that would cost $223 in a store for only $63, according to Good Morning America. (This doesn't seem like too much of a steal, but maybe there are special credits?)
Of course, this could be an amazing option if your children go to many fancy functions at Clara's house, and you don't want to shell out $375 for a child tuxedo (which is how much one cost when I was a kid. My grandpa tried to buy me one and I looked amazing, but $375. Probably $2000 today). And the cleaning is included...but I can't help but think that kids should just wear hand-me-downs forever. Or at least until they learn that their pants are not an emergency toilet.