User blog comment:ThatGuy456/A Guy's Thoughts: (Week 4) "New Amazing World of Gumball in February!"/@comment-28146494-20170305000201/@comment-30307603-20170305001555

@Valer The problem is that Gumball never really cared about Rob until "The Disaster", and even then, those events were wiped away from everyone's memory except for Rob. There's no real reason for him to care; even if his desire to be involved in everything is getting the better of him, would it really be enough of a drive for him to remember Rob is he was already so forgetful?