My son wanted to be a T-Rex Skeleton for Halloween this year, and he insisted that I be a Pteranodon skeleton with him (daughter and husband were an inflatable T-Rex and Pteranodon, making for a “museum exhibit” when we were all together). I made everything for my costume, the bones on the shirt are white HTV that I freehand cut out referencing a Pteranodon fossil, the rest is muslin, string, and black jersey fabric from my scraps bin. I used polyfill and corrugated plastic to provide form. My son insisted that his skeleton PJs were close enough to a T-Rex body (so if his costume isn’t home-made enough, just count mine as the entry to this contest). I made his T-Rex skull mask, toes, and claws out of some soft packing foam we had in the garage. I made some black mittens to sew his claws to. The tail is more muslin and black jersey. No patterns for any of the pieces, I just made it up as I went along.
This is the best full group picture we got (faces photoshopped out because we don’t do identifiable pictures of ourselves or our kids on the internet…not that they were super visible anyway)