Our ex-daughter-in-law had a child with her new husband. We sent a gift for our grandchild and she returned the gift and was very critical that we did not send a gift for her infant daughter. Do we have a responsibility to acknowledge her daughter when we have no relationship with her. We have never met her as we are not welcome at her home. We only see our grandson when he is visiting our son and this is very rare as he lives 1500 miles away.