Piper was 3 in September. I tend to measure her more than the other kids to keep track of her growth - she was so small when we brought her home. I measured her today & she's 35 1/2" tall - according to the (American) growth charts that is the 5%. She is now in mostly 2T pants (as you can see in the pic below - her GAP 2T's still need to be rolled) and either 2T or 3T tops (depending on the brand). I looked back at the other kiddo's heights and on his 2nd birthday, Coop was already taller than Piper (35 3/8"), on his 3rd birthday he was a whooping 39 1/4"! What are your 3 yr olds measuring?