Call me cynical but:
Misuse of "their" seems like an amateur mistake...
If his "son" who's name is Jerry came across the game, why did he create the account robinrobin1? I don't think it's very likely he just decided to name it after his dad...?
Perhaps this person is younger and simply looking to refine his image from past behavior and instill an assumption of maturity regarding him into the public...
Of course there is another possibility i'll not mention just yet because i wouldn't want to provide an easy way out
Food for thought.