Who buys children's clothes where?
one of the most popular children's clothing stores here is carters. it's almost in every shopping mall (I judge by São Paulo)
the prices are high, the quality is average
there is also alo bebe - the clothing there is generally okay, but there are options for those on a budget.
also, in the shopping malls, there are a number of non-chain children's clothing stores and other goods, you need to go and check them out