Usain Bolt on Sunday introduced his newborn twin sons to the world, the BBC reports. It's not clear when exactly Saint Leo Bolt and Thunder Bolt were born, but they join older sister Olympia Lightning Bolt, who was born in May of last year. The Olympic champion, 34, and partner Kasi Bennett, 30, have been together six years, ITV reports. Bennett posted a few similarly adorable pictures of the family to her own Instagram account. (And for those wondering why the couple chose Saint Leo for one of the boys, ABC.net notes it's a nod to Usain Bolt's middle name.) Bolt remains the fastest man in history, with world records in the 100-meter and 200-meter, but the Jamaican sprinter retired in 2017. (More Usain Bolt stories.)