>>58134115
I was giving my own viewpoint of how I'd feel as the father of an isekai child, not giving a character judgement on whoever the people in the pic were.
But thinking on it further, it really would depend on how my relationship with the kid turned out. I fully believe a parent is responsible for having a good relationship with their kid, so if I didn't have a good relationship with them I would assume that it was my fault somehow and feel really guilty. If I then found out that it was because they were never even my child at all I would be furious. Wouldn't be fully logical about it, but no parent can be objective on the subject of their own children. And despite everything I would still consider them my child.
If I had a good relationship with them on the other hand... I guess I would be a little hurt for not being trusted with the truth, but I would still love them as my child.