megas_sephiroth
Pro Adventurer
I don't know. To me, considering how much Sephiroth held Gast in such a high regard, he could have been laughing at the thought that Gast was really his father, but what loving father would leave his son to the hands of a psychotic made man just for a simple identification mistake. I'm more pissed at Gast than Lucrecia, because he wasn't willing to face his mistake and take responsibility for what he started.
Well, at that point he had to save his family from Hojo, right? I don't remeber that part of the game very well...
One could argue that he should have brought Sephiroth along when he escaped, rather than leaving him with Hojo. Of course, that would have ShinRa chase them everywhere, which they did in anyway.