His father Pete Conway said: “Where have 50 years gone?
“It’s been a whirlwind, but what a pleasure. Absolute pleasure.”
Mr Conway said Robbie had had “an incredible journey” and was lucky to do it with him.
Among his son’s favorite songs was Angels, which Robbie sang to him in the car on the way to Nantwich, Cheshire, shortly after writing it.
“It’s kind of an established Rob,” he said of the 1997 hit.
The star spent six years as a member of boyband Take That and became a superstar after going solo in 1996.
Looking back on 50 years of his life was a bit strange, his mother said.
“With Robert, from the time he was born until now, there have always been things going on with him,” she said.
“You were never surprised by anything as he grew up.”
When asked to identify moments in her career that have made her proud as a mother, Ms. Williams said it’s “always trying my best.”
“He always gives when he works. I can’t say that there is something that is better than the other,” she said.