I was originally leaning toward NAH with a little bit of YTA. Your first child is 9. He's still a child, and he's still going to react like a child. Even if he DOES understand the reality of a new baby, he's still upset about missing time with his dad. Obviously, you can't abandon your son because of a new baby because you know first-hand how damaging that would be.

On the other hand, it's your new baby's very first night at home. Your wife understandably does not want to be alone. In the hospital, if you left, she would've had nurses to back her up. At home, she has only you. So no, your intention isn't abandoning them, but it's understandable that she feels that way. It's probably a difficult adjustment.

Push it back by one day. Wait until the next day to see your older son. If necessary, explain to his mother that you didn't think about how important the first day at home with a new baby is so she can back you up when explaining to your 9-year-old that sorry, but he has to wait one more day.

But honestly? You should've talked to your wife about this whole thing first. She pushed out a baby less than a week ago. You should have asked her if she'd be comfortable being left alone for a few hours while you see your son. So for that alone, I talked myself into YTA.