Should I allow him to be there..

Ok so I’m currently 31 weeks pregnant and my fathers son has only been around maybe once at the first of the pregnancy. When we had the 1st ultra sound done he was there, but since then I haven’t seen him. He barely texts me or ask how I’m doing..He has a new woman in his life, I’ve tried to keep him updated but when I text I hear nothing back. I want my son to know his father but if he can’t be there for me during the pregnancy how do I know he’ll be there once he is born..Any suggestions?!