Sir Elton John has admitted that he once "burst into tears" when he made a stark realisation about a massive change in his family. In a heartfelt admission, the 'Rocket Man' singer, 78, opened up about a touching moment involving his 14-year-old son, Zachary, who attends a prestigious public school in England.

Yet, when it came to waving his son off to boarding school, Sir Elton, who shares another son, Elijah, 12, with his husband, David Furnish, was left rather upset by the experience.

Sir Elton admitted that when he arrived home, he "burst into tears" as the penny finally dropped about his "boy" and shared his thoughts with David, reports the Mail. Sir Elton said: "Our eldest son went to boarding school. We had lunch and I came home and burst into tears. I said to David, 'I've lost my boy. I've got a little man now'."

It comes in the wake of a heartbreaking health announcement made by the 'Tiny Dancer' hitmaker last year regarding his vision, with Sir Elton revealing that he'd "lost" his eyesight.

At the time, he was attending a production of The Devil Wears Prada on London's West End, but David led Sir Elton off-stage, and the legendary songwriter admitted to fans that he "cannot see the stage".

Sir Elton said: "As some of you may know I have had issues and now I have lost my sight. I haven't been able to see the performance but I have enjoyed it.

"To my husband who’s been my rock because I haven’t been able to come to many of the previews... it's hard for me to see it but I love to hear it and it sounded good tonight OK. Thank you for coming!"

Sir Elton and David have been an item for many years. They entered a civil partnership in December 2005 and later married in 2014, when the UK legalised same-sex marriage, reports People.

The couple had their first son, Zachary, in 2010 through a surrogate, who would also carry their second son, Elijah, born in 2013. The children would later serve as ring-bearers at their parents' wedding.

Speaking on The Ellen Degeneres Show in 2016, Sir Elton opened up about his husband and two "beautiful" children, explaining how life "throws you challenges".

He said: "If you'd had said to me 10 years ago I'd be sitting on your show married to the man I love and have two beautiful children I would have said, 'You put acid in my drink.' But life throws you challenges and life throws you curveballs — great curveballs."