Do you wish your first child lived and the second wasn’t born?

My dad got very drunk recently and I found him crying downstairs and gave him a hug and out of nowhere he said that he wished I was my sister, who died of heart complications before I was born- she was an accident and my parents wouldn’t have had me if she’d lived.

He kept talking about how she would have only been a few years older and how he wished she was here and not me.

I’ve always known I was a little bit second best but I never thought he’d actually regret my existence.

Is this a normal reaction to losing a child? I understand that he wishes she’d lived but he explicitly wished that I didn’t exist.

He says he didn’t mean it, but I know how he is- he gets truth serum drunk.