But according to Federer, the four children “didn’t know” about just how good their father is until recent days.
“For a long time, my four children had no idea what I had achieved during my tennis career,” he said in a recent interview.
“It was their friends who revealed to them that I was No.1 in the world.
“They were literally speechless. My victories have never been an important topic at home.”
Last year, Federer made the sad admission that he’s always struggled to get his children interested in tennis.
“I have struggled with my children. I have tried to promote tennis at my household with playing a lot of matches against Rafa, Novak and everybody but my kids don’t care,” he said.
“They need daddy home from the practice or from the matches.
“We tried to put a racquet in their hand and a ball in the other and see what happens.
“You see very quickly if kids like to play with the ball or go running outside. I think you see the differences very quickly.”
The Swiss legend said he would be able to resume running in January and return to training on the court in March or April.
However the 40-year-old said he’d be “incredibly surprised” if he was even ready for Wimbledon in July.
“Even before the operation, we knew that a break of many months would be necessary afterwards,” he said.
“I have started a long rehabilitation process in which I put all my heart and soul. But the situation is not the same as in 2016.
“I need to be very patient and give my knee the time to heal. The next few months will be crucial.”