Any mom of a 6-ish-year-old girl who's shopped for clothes with her daughter eventually stumbles across this puzzling conundrum: What's the difference between size 6 and 6x? The reason this is such a head scratcher is it's the only size that has an "x" version. There's no 5x, 7x, or 8x ... so why 6x? Even more mystifying is the fact that there's no 6x in boys; it's just a girl thing. What's the deal?

According to Dyone Cupples, owner of a children’s online consignment boutique TheNextSizeUp.com, "Generally a 6x runs slightly larger in width and length than a 6 -- it's like a 6 and a half. It seems to fill a gap in sizes where many girls fall."

The reason 6x is the only "x" that exists is because 6 is an age when many kids -- particularly girls -- shoot up in height, says Booth Parker, owner of Haley and the Hound, a women's and kids' clothing line. "A lot of brands have little girls' clothes up to a 6 and big girl styles start at a 7," she says. "So the 6x allows girls to look their age even if they are tall."

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Boys' clothes don't come in 6x because they have different growth patterns -- and because boys' styles tend to look fine on varying sizes. And let's face it, boys aren't generally as style-conscious as girls. "Once boys turn 2, they are out of jon jons and into polo shirts for the rest of their life," says Parker. "Plus, boys don’t seem to care if the shirt runs a little big in order to be long enough."

Do you think size 6x is essential for girls or not?


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