Have you tried cotton wraps? i had them with my son and even tho it was hot weather at night he was only in a singlet and nappy and his wrap. and he was fine and happily sleeping

On the dummy sidei cant help as my bubbs didnt have one. but maybe 4 mths is a bit young tog et rid of a comfort thing....maybe try when you're bubbs is a bit older..

you just do whatever works for you and you're bubbs...