Boyfriend/Babyddy Other Child

So my boyfriend which is my 5 year old daughters dad and i have been in a relationship for 1 year now.We been on and off these past 3 years.During one of our logest breakups he pregnated a girl who he was just having sex with.Now we are together been together for 1 year and the child is 1 and 5 months.He has not met the child nor has any communication with the girl due to the fact that she is completely Psycho and in denial/obsessed with my bf.Also her dad is a crazy man and will literally go off on him..So what should i do or say? I dont prevent him or jave ever told him he cant see the child he chooses not to.He is planning on going to court to settle childsupport and he wants her to have full custody.