I have use a lot of the sleep sack in the past , and they have be great . I buy the `` walker '' version for we 19 month old , since she obviously need foot hole so she can walk . I read other review that complain about these be way too big , and wow be they right ... I buy the large -lrb- 12-18months -rrb- because people say they run big . here be the rundown on the size - Sleep Sack be 12-18months , suppose to fit 30-35 inch , and 22-28 lb . we daughter be 19 month , 32 inch , and 23 lb . THIS THING be HUGE !!! I try it on she , and the bottom part all the way around just drag all over the floor , a literal pool of material at she foot . she can walk , but eventually trip over all the material . she be not able to stand up on she own because she step on all the extra material around she foot , and be basically pin down by it . so disappoint in the size . if the 12-18 month size be way too big for my above average height 19 month old , there be no way it would fit most 12-18 month old . the large be the smallest size with foot , so this have to be return . if the size be better , I would love this .