I am assuming the stocking is a knee high. Is the whole stocking stretched out of shape or is it just the top that needs to be taken in to hold it up. Put it on,pull it up to the right height then use a safety pin on the outside to adjust it until you get it tight enough. You may need 2 pins and you may have to adjust it a few times till you get it tight enough. Does the stocking have a rubberized top? I had a pair of thy highs like that. They were fine when I first put them on but after they wouldn't stay up. I wouldn't sew and cut off to extra. If the pins work and he wears long pants you won't see it. This way your Dr will see what is happening and maybe have a better way to solve the problem. Sometimes a velcro strip will help but if you have a garter belt that works even better as it is adjusted at the waist