Can anyone recommend where to get bottoms for a boy. He will not wear trousers with stiff material or zips, buttons etc and is only happy in sweatpants type things which after numerous battles and water money I have accepted. Problem is he wear though them at a pace of god knows what. HandM, Gap all get beg holes on his left knee. Only the left knee funny enough. It ends up quite expensive and such a waste as the rest of the trousers are okay. I don't sew so can't fix anything to save my life. Any suggestions for durable joggers please?