“This trip was particularly brutal, because coming from Dubai was a 12-hour time change,” Federer said. “So the first night was unbelievable. One of my daughters slept from 8 to 12 and then didn’t sleep from midnight all the way through, and I was like, I can’t believe it.”

The traveling Federers manage it all with the help of several nannies. “We have a few just to make sure they don’t overwork as well and that we have a good vibe,” Federer said.

They also manage it now that Charlene and Myla are of school age, with the help of a kindergarten teacher who accompanies Federer and his wife, Mirka, on the road and instructs the girls most mornings in hotel rooms or other spaces converted into classrooms.

Federer said that the kindergarten teacher had a degree for teaching primary school and that the plan was for the girls to begin the equivalent of first grade on the road later in the year.

“It seems like the right thing to do, so we can all stay together,” Federer said. “I wasn’t sure if that was what I really wanted for the kids at the beginning, but I must say it keeps us together.

“The girls enjoy it, and I love being with my family, and so does Mirka. She loves being with me, so we get to see each other every single day, basically, and I think that’s more important than being apart from each other and them going to normal school at the moment. But things can change very quickly.”