Here's how clothes work. When you're a baby, you wear baby clothes. When you're a kid, you wear kid clothes. And when you're an adult, you wear adult clothes.
Here's how life works. Your body grows on its own terms. When your body gets to the point where you need to upgrade clothing departments, you have to just go on and go for it. There are three-year-olds who wear size 5 and there are seven-year-olds who wear size 5. And yes, there are eleven- and twelve-year-olds who wear adult clothing.
The problem is the transition phase. People never want to accept that it's time to move up.
I don't know if they're actually in denial about the fact that their children are growing up or if they just want to avoid paying more money for the adult clothes, but it's so annoying.
And if they were just asking, it would be one thing, but it's the eye-rolling and the exasperated sighs that get me. Like, how DARE you not have this in 2X? My daughter is too big for an extra large! WHAT AM I SUPPOSED TO DO?
I refuse to coddle these people. I always say something direct, like, "We only carry girls sizes through extra large, you might want to try moving up to women's sizes." When they balk at this suggestion, I tell them that a 16 in girls is equivalent to about a 2 or 4 in women's. This is accurate (at Old Navy at least) but they tend to get really defensive. "No way," they tell me. "She has to be like, a double zero or something." This is a stupid assumption. Did you expect there to be a gap between extra large in girls' and extra small in women's? That wouldn't be very smart on a clothing company's part, would it?
If they're really insistent, I'll eventually cave and tell them we carry some XXL online, but we don't have it in everything and they shouldn't want it anyway!
Your child is too big for children's clothes! I'm sorry if this makes you sentimental or sad, but it's just the way it is. Take her to the women's section and shop there. Sorry I'm not sorry.