Sir Elton John welcomed some of Hollywood's biggest names to his 21st Annual Academy Awards Viewing Party - along with his two-year-old son as guest of honour.
Over the past two decades, the event has raised nearly \$34m for HIV and Aids research.
On the red carpet ahead of the party, the musician explained how the money has helped improve the lives of those living with the conditions.
"The thing is, it's a very treatable disease now," he said.
"We've come so far medically that you can treat the disease and it's easier than diabetes.
"It's much simpler and people shouldn't have that stigma, but we need to have more compassion from people for one another.
"Every family must know someone who's had HIV and Aids."
Among the celebrities attending the party alongside Sir Elton and his partner David Furnish were singer Miley Cyrus, reality TV star Kim Kardashian, rapper Nicki Minaj and chef Gordon Ramsay.
Guest of honour was the couple's son Zachary Furnish-John who met the A-list guests dressed in a mini tuxedo.
But the little boy's parents were quick to insist he would not be staying out too late.
"We'll make sure they get home in time for their regular bath time, and story time with the nanny," Furnish said.
"Then we'll see them tomorrow morning, when we get back."
Zachary, who was born to a surrogate mother in December 2010, was joined in the Furnish-John family by younger brother Elijah earlier this year.