Jay-Z says he cried with joy when his mum came out as gay to him.
She only confirmed the news eight months ago, when he was recording his latest album.
The rapper has been speaking with David Letterman on the veteran TV presenter's Netflix show My Next Guest Needs No Introduction.
Jay-Z told the host: "Imagine having to live your life as someone else, and you think you're protecting your kids.
"For my mother to have to live as someone that she wasn't, and hide and protect her kids, and didn't want to embarrass her kids for all of this time... and for her to sit in front of me and tell me 'I think I love someone'... I mean, I really cried.
"I was so happy for her that she was free," he added.
After the conversation with his mother, Jay-Z wrote a track called Smile - which includes the lyrics: "Mama had four kids, but she's a lesbian/Had to pretend so long that she's a thespian. Had to hide in the closet, so she medicate/Society shame and the pain was too much to take."