It could be...my dd never *looked* insanely big for her age..because she wasn't...she was between 50-75th percentile, so just a bit over average, in overall height...but her TORSO, which can be really hard to tell with clothes on, especially like a dress or long untucked T shirt, was VERY long...and it really only does take an inch or two in TORSO to make a GINORMOUS difference in how a child fits into SEATS....but an inch or 2 difference in OVERALL height is nothing really.... I learned to expect that her torso height tended to be equivalent to the TORSO height of children 6-10 inches taller, OVERALL than she was. We haz short chicken legs lol.
Here is a pic of my friends child, in his outgrown marathon..he is 2..almost 3, but still 2 years old. Yes, it's a marathon. And then a picture of him in the regent she bought him, at age TWO, because he was so big. MY friend is 6 feet tall, her husband is well over 6 ft tall, they are very large poeple. (i haz permission)