Katy Perry's still got love for her ex -- and his family!

The Witness singer left a comment on John Mayer's Instagram on Wednesday after The Search for Everything singer-songwriter shared a sweet snap of him and his dad in honor of his pop's 90th birthday.

"Happy 90th Birthday, Dad! Leave doting comments about my dad below," Mayer, 39, captioned the pic. "He’ll love scrolling through it. Also please stop this train. Thank you."

MORE: Russell Brand Says Marriage to Katy Perry Was 'Very Wonderful,' Wishes Her 'All the Best'

"Looking fantastic as ever!" Perry commented. "Happy birthday friend."

MORE: John Mayer Responds to Katy Perry Calling Him the 'Best Lover' She's Ever Had

A happy 90 years, indeed!

Mayer, who openly spoke about his former flame's influence on his most recent work earlier this summer, shared what song about an ex makes him so sad, he can't play it live anymore.

Watch the video below to find out which one.