My sister and brother are way taller than me!! What happened!?!?

Asked: My sister and brother are way taller than me!! What happened!?!?My little sister and brother have grown literally like weeds since the last time I saw them, New Years.My sister is now about 5'11 and has completely morphed from the nerdy girl to apparently an amateur model. My brother, who I use to toss around playfully, is now 6'4 and built like a superhero!! I haven't grown a bit since 15(4 years ago). They're both 17yrs old. I can't figure this out. My mom is only 5'5 and my dad is just 6'0, on a good day. My mom doesn't have

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