4 year old you cries and wynes?

hello moms. I got a question and i need some advice. I have a 4 year old stepson. He will be 5 in Feburary. His fater has had him since he was about 1 1/2. Me and his fater have been together for about 7 months now. Anyways he is always crying and calling for daddy over EVERYTHING. If he don't cry he wynes. I am trying to get him to stop this and i keep telling his fater to ignore him but he always falls into it and gives him the attention. Now i know that the boy has problems-like for example his mother never gave him any attention from birth till my husband got him into his custody. She kept him in his room all the time-and if you were to mention her the boy screams bloody murder. So i know he has some phycological problems. BUT the crying and wying is getting on my nerves. I am trying so hard to ignore it but my patience is running thin. Please somebody give me some advice on how to deal with this materr PLEASE-thanks