I want to make my daughter a pair of corduroy sketchbooks to wear over tights. I'm worried about cotton shorts worn over thick cotton tights bunching up when she moves. I have some sort of mystery polyester lining in the right color in my stash. Is there a reason I can't just interline my shorts, cut the lining shorter, and catch them in the hem? Or should I be doing two separate pairs with separate hems only treated as one at the waistband?