That's a "sticky" problem:) LOL....ok, bad joke. I think GOO BE GONE works on clothing and maybe even WD40..Just wash them right away to keep the oils from sticking. I'm not positive that it works for clothing, but WD40 and some elbow grease removed sticky silly puddy from my carpet and didn't leave any residue. Maybe the Queen of Clean has an answer...www.queenofclean.com
As far as pants for your daughter. I love the pants that have the adjustable waist inside. The length always fits perfect for my tiny 3yr old, and if the waist is too big, I just tighten up the elastic on the inside of the waist and they fit perfectly. You can find these at The Childrens Place. They often have great sales.