The actor and musician was in attendance — along with his wife Ashlee Simpson, their 𝘤𝘩𝘪𝘭𝘥ren and his siblings — as his iconic mother took the stage at the weekend charity event in Aspen

Evan Ross and Diana Ross. Photo: Pascal Le Segretain/Getty

For Diana Ross, life is endless love — at least according to her son, Evan Ross.

“Her whole thing is love,” the musician, 34, told PEOPLE of his mother while at the Aspen Snow Ball over the weekend. “My mom doesn’t do things for any other reason other than love.”

He continued, “And I would never speak for her, but I know that for a fact. It’s never about money. It’s never about… It’s about love. My mother’s like, she cares about her 𝘤𝘩𝘪𝘭𝘥ren, she cares about her grand𝘤𝘩𝘪𝘭𝘥ren. She cares about people in general. And she’s beautiful. That’s about it.”

During the event on Saturday night, the 78-year-old mother of five and grandmother of eight performed as she reunited with much of her family for the charity gala — held at the St. Regis Aspen Resort, despite a snowstorm altering the celeb-studded guest list.

Diana Ross Says Her ‘Heart Is Filled with Joy’ as She Celebrates Her 78th Birthday with FamilyEvan Ross and Ashlee Simpson. Nikki Hausherr

The event, which supports Gabrielle’s Angel Foundation for Cancer Research and the launch of Children’s Oncology Support fund founded by film producer Thomas Pierce, honored Ross’ longtime friend Denise Rich, who has hosted the annual Angel Ball in New York for over 25 years.

“My mom loves 𝘤𝘩𝘪𝘭𝘥ren and she loves people that are trying to make a difference in a big way,” Evan told PEOPLE. “She’s known Denise Rich for a long time too. And all the pieces made sense. It just happened to work well,” he said of Diana’s involvement in the event. “But certain things are meant to be and it was meant to be.”

Evan’s wife Ashlee Simpson and their 𝘤𝘩𝘪𝘭𝘥ren were in attendance, as well as honorary chair Marcia Gay Harden, Macy Gray, Rhonda Ross Kendrick and William Abadie — in addition to international celebrities, philanthropists, and notable guests from all over the world who helped to raise $2.5 millions dollars for the cause.

Diana Ross’ Cutest Moment With Her Grand𝘤𝘩𝘪𝘭𝘥renMatthew Baker/Redferns

“I’m so happy we’re all here,” Evan added. “We’ve been coming to Aspen for years and it’s a happy place. It’s a beautiful thing to do together.”

Celebrating special occasions with her big family isn’t new to Diana.

The entertainer — who is also mom to Tracee Ellis Ross, Chudney Ross, Rhonda Ross and Ross Naess — celebrated her 𝐛𝐢𝐫𝐭𝐡day with the entire family last March.

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“I am so grateful for all the blessings in my life for there are so many. I am very proud and happy, I have so much to be grateful for,” she wrote on Twitter alongside a family photo. “Thank you ALL for your 𝐛𝐢𝐫𝐭𝐡day wishes, my heart is filled with joy and so much love.”

The previous Christmas, the legendary singer shared a photo on Twitter from her family’s holiday celebration. “So so many blessings , sending Love to our Global family , do your best to stay safe I love you wonderful Christmas time,” she wrote alongside the family photo.