Fabio, currently on loan at Loftus Road from the Red Devils, sat out Saturday's Premier League encounter.
He told Globoesporte: "I was pleased to see my brother score a goal like that. Naturally I wanted to celebrate. But I was sat next to the QPR president!
"I told him afterwards: 'You never score goals like that! You had to do it against my team!" But I was happy for him.
"I've grown a lot this season. We've both matured. He's flying [for Manchester United] and I'm playing more. The change has been good for us."