Alicia Keys paid a moving tribute to Whitney Houston at the late singer’s funeral yesterday (Feb. 18). Prior to her musical performance, Keys, visibly devastated by the loss Houston, offered some endearing anecdotes about her experiences with Houston during her tragically short life.“We came up with this funny nickname for each other,” Keys revealed about her relationship with Houston. “I don’t even know where it came from. “She called me Mema, and I called her Mema. Whenever I’d text her, I’d say, ‘Hey Mema!’” Keys said, wiping her eyes.

Keys then revealed a haunting but beautiful moment she shared with her son, Egypt. “Just last night when we were getting ready to get on the plane and come back, my son said, ‘Mema! Mema! Mema!’ He kept saying, ‘Mema,’” Keys said, her eyes widening. “He didn’t know that. I just thought that was beautiful,” Keys said. “I just felt really surrounded by her.”

Keys let out a heavy sigh. “I just think it’s so obvious, the way she just crept into everybody’s hearts,” she said, breaking to grab some more tissues, “and the way that she was just such a beautiful human being. A really caring, beautiful human being, who would call you for no reason at all — just to say ‘hi.’ And that’s rare.”

Just before launching into a roaring, tearful rendition of ‘Send Me an Angel,’ Keys went on to reflect on Houston’s efforts to give back and reach out to all the artists lucky enough to work with the legend. “I just think she’s been an angel to us,” Keys said, “and I think we’ve been sent an angel for a long time.”

Watch Alicia Keys Perform at Whitney Houston’s Funeral