Have you told your DD that it is ok for him to use your quilts? It may be that she wants them to stay "nice" so he has them when he is grown and has children of his own.
Maybe you could make him a "nice" one she could pack away and he can use and love the rest of them.
Or, have him pick the fabrics and make it irresistible so she has no choice but to let him use it! lol