My favorite clothing store for kids is actually H&M. They have a killer selection of simple and adorable graphic clothing for modern kids. For funsies I made a few boards of outfits that I'd match the kids in if I was the type to match children. Which by the way I totally am. I don't do identical outfits but I tend to put them in the same color family or similar themes, especially if I were to take them somewhere like say...
Horton's Hayride or other Musical Events
The LA Zoo
A Church Picnic or Spring Wedding
Knott's Berry Farm
I made these boards months ago and then you know... the kids. They took over.