TORONTO - Canadian singer-songwriter Rufus Wainwright says he's been "overwhelmed with happiness and joy" since the birth of his daughter earlier this year.

Viva Katherine Wainwright Cohen, the offspring of Wainwright and Lorca Cohen, the daughter of Canadian music legend Leonard Cohen, was born on Feb. 2 in Los Angeles. Wainwright has also dubbed his partner, Jorn Weisbrodt, "deputy dad."

Wainwright calls parenthood a "wonderful, incredible voyage."

He says having his daughter was a life-altering experience that has helped him deal with his mother's death.

Kate McGarrigle died on Jan. 18, 2010, about three years after she was diagnosed with sarcoma, a rare form of cancer.

Wainwright has since worked to support his mother's cancer charity, the Kate McGarrigle Fund, and other causes he feels passionate about, including the fight against AIDS. On May 3, he's taking part in a charity concert organized by the Stephen Lewis Foundation in Toronto called Hope Rising, along with Alicia Keys, Angelique Kidjo and other musicians.

"It's an AIDS charity, and although it's mostly focused on Africa, certainly being a gay man in his 30s I am deeply, deeply intertwined with the AIDS saga, to this day," Wainwright said of his interest in the project.

Money from tickets, which range in price from about $160 to $2,500, will support grassroots organizations at the frontlines of the AIDS pandemic in Africa.

"We want to actually do something concrete, so I think Hope Rising is a preview of great things to come ... and I feel very, very fortunate to be able to asked to do this."