Out singer-songwriter Mary Lambert defended her lesbian mother while growing up.

The 24-year-old Lambert, the featured vocalist on Macklemore & Ryan Lewis' gay marriage anthem Same Love, was joined by Madonna at Sunday's Grammys performance of the hit song.

In an interview with Access Hollywood, Lambert said she was six when her mother came out.

“It was fine,” Lambert said. “I don't think you really understand totally what's going on. It's just like mom's dating somebody new. The divorce was difficult, you know, my parents' divorce. But as far as sexual orientation, it's like, you know, you can understand at a really young age how universal love is. It wasn't until I was in middle school or in grade school that I was like, 'Oh, okay, I'm weird now.'”

(Related: Mary Lambert and Michelle Chamuel are dating.)

“I've always been outspoken. And I was always championing everybody. 'You can't say the word gay in a negative way, my mom's gay.' And then it turned out everybody called me a lesbian behind my back when I was in fifth grade. And then, of course, I came out.”

(Watch the entire segment.)