He called her a mistake

Me and my boyfriend were having an argument and I asked what about our daughter? and he said that was a mistake. after I showed that I was clearly upset about that comment he tried to take it back but I wouldn't hear it. I don't know what to do. I'm very upset about it and I'm not sure if I should leave him or try to hear him out and work through it. it really hurts that he said that and it make me feel like he doesn't want her which is super hurtful considering he already has two other kids.