Roger Federer is one of the greatest tennis players, but when it comes to coaching, especially his kids, he admitted he's nowhere near No. 1. Federer is married to Mirka Federer, and the couple are parents to four children: two sets of twins.Leo Federer (born in 2019) wanted to come to Shanghai and watch the Masters event unfold. Federer fulfilled his wish by tagging him along as they jetted off to land in China.On Wednesday, ahead of his celebrity doubles game in Shanghai, Federer attended the "On Thanks for Playing" event, where he, alongside officials from the Shanghai Xuhui District Sports Bureau, opened newly renovated tennis courts at the Shanghai Xuhui District First Youth Amateur Sports School. At the event, he explained the importance of great junior coaches in nurturing a young player’s passion for the game."On him, or if it's on the other kid or the coach who's there because of my success and my know-how, the expectations are so incredibly high at the professional level," Federer said. "Everybody thinks I'm equally good as a coach for an 11-year-old, but I'm not. So that's where I need to rely heavily on the junior coaches, who do amazing work.Federer thanked his own former coaches and junior coaches from whom he learned about the sport. He can feel their importance now that he has seen it all, testifying to the time spent early on helping him pursue a great tennis career."I'm always here to thank all my former coaches and junior coaches, who are so important in inspiring kids," Federer added. "Having great coaches when you're young is really important to feel the love for the game, and that's where Leo has had great coaches so far. I've not been the number one coach; I just try to help out.Federer admits that "it's tough being a parent on the tennis court." The 20-time Grand Slam winner relishes not thinking too much or pushing his kids too hard."When they travel, you don't push too hard; they don't have to work, they don't have to study, and they don't have to think about professional tennis -- they just relax," Federer added.Roger Federer in Shanghai for "Roger & Friends" celebrity doubles matchOn October 10, Roger Federer will take part in the "Roger & Friends" celebrity doubles event, marking his first appearance in Shanghai since 2017, when he won the men's singles title.The Swiss legend will team up with actor Donnie Yen, actor Wu Lei, and former Chinese tennis player Zheng Jie. The exhibition match will take place at the Qizhong Stadium.