(CNN)The bond between a father and his kids can be extremely powerful.
In sport, a dad's duties can range from shipping their kids to practice, buying the necessary kit and spending countless hours supporting their children.
During that time spent together, the relationship can deepen, and in the public pressure-cooker that is elite sport emotions can bubble over.
So on Father's Day, CNN Sport looks back at some memorable dad moments.
When up late watching TV one night in 1980, Richard Williams turned the channel to see Romania's Virginia Ruzici receive a check for winning a tennis tournament that he describes as "a hell of a lot of money for four days' (work)."
"I went to my wife and said that we have two kids, and we'll become rich. They're going to be tennis players," he said, referring to daughters Venus and Serena.
A 78-page blueprint was soon prepared, describing how Venus and Serena would reach the top. A key plank of the plan was that it would be enacted from one of America's roughest areas.
The Williams family was not poor and could have afforded to live in more well-to-do areas. But it was decided that Compton was the best place for their early education.
"There was no place in the world that was rougher than Compton," Williams said. "The ghetto will make you rough, it'll make you tough, it'll make you strong.
"And so that's why I went to Compton with them."
The plan turned out quite well -- at the last time of counting Serena has 23 grand slam singles titles to her name while Venus has seven, despite suffering from illness and injuries in recent years.
Mahut consoled on court by son
It was a fairytale run at the French Open this year for Nicolas Mahut.
Playing in his hometown Grand Slam, Mahut put on a show for the Parisian crowd, including his first-round win against Marco Cecchinato, where he lost the first two sets only to come back and win the match in five.
But in the third round against the Argentine Leonardo Mayer, Mahut came unstuck, eventually losing 3-6 7-6 6-4 7-6.
While packing his bags, emotions got the better of the Frenchman as he broke down in tears.
At which point Mahut's seven-year-old son Natanel ran on the court to embrace his father. The pair shared a hug and then walked off hand-in-hand to the applause of the crowd.
Watching on, even the victor Mayer became emotional and joined in the clapping.