Size differences

Isn't it interesting how children grow so differently? My youngest daughter went from NB diapers to S in a couple weeks, by 2 months, she was in medium. By the time she was 6 months of age, she wore larges. When she was 2 I had her in XL and was worried she'd outgrow those as well (there isn't anything bigger with cloth diapers than XL, and even those are rare). She's 3 now and wears a size 4T in clothing.

My son, on the other hand, is nearly 12 months of age and still fits into size medium diapers comfortably! I admit, at first I was concerned, he looks small to me. Much smaller than I'm accustomed to seeing at his age. He eats fine, nurses fine, and is otherwise quite healthy, so I stopped worrying about it. It could be that he's just going to be smaller framed. Or it could be that he's growing more slowly. Or it could simply be that he is more average than his older sister, who was above average for growth in her first year.