My son is 20 months and he’s having issues with sleep sacks. Always puts his arms in and gets twisted, stuck, etc. I’m tired of buying more and trying them out, we’ve tried a ton of different kinds. I was thinking maybe I could put a top blanket on his crib mattress? I know he’s old enough for a stuffy and blanket in the crib, but I mean more of actually tucking in a blanket and him using it like he would in a bed. I’m just worried he’s not going to know how to use it and get even more frustrated when he can’t get it on right or gets it off entirely. Any success with this?