Judy Murray says playing with a smile on his face was the key to Jamie Murray winning the Wimbledon mixed doubles title with Martina Hingis.
They beat defending champions Heather Watson and Henri Kontinen 6-4 6-4 in last weekend's final.
Murray won the same title with Jelena Jankovic 10 years ago.
"I remember in 2007 his coach Louis Cayer saying to him that the key to mixed doubles is to keep your partner happy," Judy Murray told BBC Scotland.
"The two of them - Jamie and Martina Hingis - they smiled the whole way through it in the same way he smiled the whole way through it with Jelena Jankovic all those years ago.
"It was an amazing way to finish the championships - the last match on Centre Court and huge crowd to see two Brits in the final.
"It was 10 years on from Jamie winning the mixed doubles title the first time, pretty much as a rookie 21-year-old.
"It was a wonderful thing because, for any British player to win a title at Wimbledon, is the icing on your cake."
Murray did not want to be drawn too much on the latest condition of her other son's hip injury, but she did express quiet confidence that world singles number one Andy will take part in the US Open in August.
"We'll and see what him and his team decide," she added. "He needs to have a period of rest and recuperation.
"But fingers crossed he'll be there."