I have seen some crazy growth spurts at young ages that don't necessarily mean they will be freakishly oversized as adults.
My cousin Emily was absolutely huge in Elementary, both height and weight. When she played on the 3rd and 4th grade T-Ball teams she was bigger than some high school girls. But the thing is she sprouted really really quickly and then just tapered off.
Now she is a full adult, mom of her own and sure she is tall for a woman, she is right around 6 feet even but she isn't freakishly tall or big but she absolutely DWARFED kids in Elementary.
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