I bought these in a size 8 for my 23 month-old daughter (who currently wears a size 7 to 7 1/2), and while they fit her feet (with room to grow) they were so tight in the calves that I could barely zip them up. She proudly wore them for about 3 minutes before complaining that they hurt. She is in the 97th percentile for height and the 93rd percentile for weight, which may translate into the feet of a 2 year-old but the legs of a 3 1/2 year-old, but neither her calves nor her thighs are chubby or particularly wide. We loved them but are sending them back - perhaps a different style of boot would work better?