can anyone relate:9 month old in size 1 shoe

is it normal that she's only in a size one at 9 months?! it's like they aren't growing. I'm just worried I'm not giving her enough nutrients to give her to grow? is that possible?! she has two healthy snacks a day, and 30 oz of breast milk or formula if I have to supplement. just weird because I'm in a size 10 and my husband wears 12. we are both pretty tall too. her two cousins that are born weeks apart from her are in a size 3. she is no where near that!