My SD is almost 20 with 2 kids of her own and she uses them against us basically if we don't cater to her wants and needs she wont let us see the kids. My biggest issue is she refuses  to work and wont support the kids or go after the fathers and wants to  move back in with us so we become responsible for there well being which im ok with taking care of her kids just not her. Unfortunately my fiance  see it differently  we have been together  21 years and are trying to plan a wedding but SD is doing everything  possible  to make sure that dont happen by moving back.