M22 – You could wash one that is already wrinkled, but stretch it out A LOT before you put it inside out on his head – I mean PULL hard to get it back to its original shape and then let it dry on his head. If you see that it’s got pockets of the velvet and it still curls at this point, then it’s probably a lost cause, but you’ll know for the future.
Yes, I used to wash my kid’s kippas, but it depends on the condition I find them in now to see if I’m going to spend the effort on washing it – like is it already turning brown from the sun or is the trim coming apart or is YT around the corner and I’ll be buying a new one anyway – that all comes in the cheshbon I make before I decide to wash one any more. Unfortunately I do have one son who has a problem with bed wetting and sometimes I have to wash a perfectly good kippa that got stuck under him during the night. So yes, it is possible. There are certain types of kippas that wash better than others, and I wouldn’t recommend washing the ones with decorations on them either, but a plain black velvet one, why not?