His Majesty Sultan Ibrahim, King of Malaysia, and Her Majesty Raja Zarith Sofiah, Queen of Malaysia, graced the opening round of the GT World Challenge Asia Series at the Sepang International Circuit (SIC) on Sunday (April 13) to show their support for their sons, Tunku Panglima Johor Tunku Abdul Rahman Al-Haj and Tunku Putera Johor Tunku Abu Bakar Al-Haj, who are racing under the Johor Motorsports Racing (JMR) team.