My son is 33" tall and almost 30 lbs and he STILL does not fit in these! These pajamas are supposed to be 18 months and while he is 19 mos old he usually wears size 24 mos. I have purchased HALO sleepwear before and never noticed such a huge size discrepancy and wanted to be sure parents knew before they bought these. I know that one day he will fit in these and I am pretty sure they will work well as long as it is cold out.