I like these because they are soft, they appear to run true to size. My 6 year old (who wears a 4-5T) fit into the XS until he had a growth spurt and now fits a S. He's very small for his age, but sizes seem consistent with other brands. They hold up well in the wash and don't shrink much. My only comment is that they are a bit on the thin side, the white isn't completely see through but it's not completely opaque either.