I bought these for my 8 month old daughter in size 12-18 months because she is a chubster (21.5 lbs) and they fit really well with some room to grow in the waist and the legs. They are extremely cute and soft. I throw them on her all the time. My one thing is I don't love the green color so if I had to purchase again I'd get the set with the two pink colors and the purple.