my fiance has 2 children with his ex (hes a bit older than me) weve been together two years and now have a wonderful daughter. he never changed his otehr daughters nappys but changed his sons and he says he feels its morally wrong for him to change and bath our daughter as shes a girl only problem is it means its always me doing it and i get up all thru the night he never has and im worn out, any advise??