Gene Simmons was not his usual self during KISS' concert Wednesday night in Brazil, where he was forced to perform while sitting down after falling ill.In video shared on social media, the 73-year-old rock star can be seen holding his bass while sitting in a chair. The one-minute video then cuts to Paul Stanley telling the audience at Arena da Amazônia in Manaus, Brazil they're going to have to stop the concert to tend to Simmons.«We're gonna have to stop,» he says. «Because we love him, right? Let's give Gene a really loud, 'Gene!' One, two, three.