The twins come just a year after the birth of their big sister.

Usain Bolt has revealed the name of his two newborn twin sons, Saint Leo and Thunder Bolt. The eight-time Olympic champion and partner Kasi Bennett recently became a family of five and welcomed the new babies with Instagram posts. Thunder's name is similar in wordplay to that of his big sister, who Usain and Kasi named Olympia Lightning Bolt following her birth last year. https://www.instagram.com/p/CQWeB5dFGB0/?utm_source=ig_web_copy_link Saint Leo is named after the retired sprinter's middle name. Kasi also posted family snaps to pay tribute to Usain on on Father's Day. "You are the rock of this family and the greatest daddy to our little ones," she wrote. "We love you world without end!" https://www.instagram.com/p/CQWelwZBOGS/?utm_source=ig_web_copy_link The wordplay of both Thunder and Olympia Lightning is reminiscent of the likes of North West, the seven-year-old daughter of Kim Kardashian and Kanye West. "I actually got it from Jay Leno, who made that as a joke," Kim previously said of the punny name in a video for sister Kylie Jenner's YouTube channel.