Robert Plant "got really old" after his son died.
The 'Whole Lotta Love' hitmaker and his then-wife Maureen Wilson lost five-year-old Karac in 1977 after the youngster contracted a stomach virus and he admitted the tragedy stopped him worrying about ageing.
He said: “I think I got really old when I was 29, when we as a family lost the key man.
"So many parts of our being, exuberance, optimism and physicality and the whole wear and tear of life has fluctuating time periods where it plays different cards for you.
"What I try and do to keep the Grim Reaper at bay is to be around people who are funny and kind. That’s the panacea for me, that helps me through.”
The 73-year-old rocker - who has Carmen, 53, and Logan, 42, with Maureen, and Jesse, 30, with his former sister-in-law Shirley - is still performing now and is proud that several of his grandchildren are also in bands of their own.
He told the Daily Telegraph newspaper: “We’ve had our time. But two generations from when I first started being addicted to this, I’ve still got a foot on the pedal, I’m still going somewhere. It’s the prerogative of a madman! Oh yeah!”
Robert's former band Led Zeppelin were renowned for their hedonistic ways and he admitted they had a "great time" together before calling it a day.
He said: “It was just dumbf***, a lot of it.
"It would be trite to say the actions fit the circumstances there on the spot at that time. We made great music. We had a great time. And then it stopped. That’s all I know about it.”
And the singer has no plans to retire.
He said: “I was 19 on the first Led Zeppelin rehearsals, and I was 32 when [drummer] John [Bonham] passed away, that awful time.
“People used to say to me, ‘Well, you must have done enough now?’ Enough of f****** what? ‘Enough to retire!’
"So imagine the blessing to be 40 years further down the road, and I still don’t know enough to stop in any respect.
"There’s always something new to learn, somewhere new to take it. I love it.”