Is he childless? My fiances children never call him except if there is money.?

His daughter from his first wife never calls him. It's been ten months since she was married. She did e-mail to let him know that she got a new job. You think she would pick up the phone and want to chat with him occasionally. His son only picks up his cell if there is money on the way to help him out with him starting out in life at a new job since graduating from college. The ex-wife is a loony tune and makes up illnesses in her head so she doesn't have to work in life and to get on disability. It is like he is childless. The kids have not warmed up to me and keep their distance. They run to their mother if she snaps her fingers. She is remarried. My fiance said his ex provides the emotional support and he provides the money. It's always been like that. I don't have any children so this is all new for me. I prefer to stay in the background. They are his children and they are adults now. I don't want to stir the pot. Do I just let him handle the situations when his children are involved.