I bought these leggings for my 14m old who is starting to crawl. He has slim legs, however these leggings are very tight and narrow fitting, definitely not for those babies who have lovely chunky thighs! I’ve also found that the knee grips don’t seem to sit on his knees but go to the side. A shame really as I wanted to love them. Haven’t returned them as I’d already washed them. The material is nice though, like a pair of warm tights