Would you be mad if your SO was there for the birth but went home as soon as baby is born?

My brother and his BM had a baby back in 2018, they moved in together for 6 months and then broke up because he wasn’t helping out much and she told him he needs to step up. He lives with my mom now (he’s 26) and after they broke up he continued going over to “see his daughter” a couple times a month (mostly when she gets paid or child tax is out). BM asked for another baby, he said not yet. She stopped her birth control and didn’t tell him and she’s now due in a week.

Problem is, he’s now asking my dad to take him back and forth between BM and our moms house. They’re having a second kid together but he won’t move back in with her or help her out. He is staying there for this week, and then going back to my moms once his son is born because her mom will be there to care for the oldest daughter.

Would you be okay with your SO being there for the birth but then going back to his mothers once baby is born? Isn’t this supposed to be an exciting time to spend as a family?

He doesn’t drive either, so he begs me or my dad to drive him back and forth and never offers gas money.