"One thing about boys' fashion is that it's more long-term and less trendy," says trend expert and StyleAuteur.com founder Lauren A. Rothman. "So there's a lot more of a classic feel in boys' clothing. A trend can last a lot longer." That means that, yes, those skinny jeans your kid still fits into are keepers. "Boys can do skinny jeans for four years, while girls have moved on already."