Princess Diana Called 'Often' Before My Mom Died of AIDS, Says Elizabeth Glaser's Son Jake

Princess Diana was known for her HIV/AIDS advocacy on the world stage, but her support didn't stop behind the scenes — especially when it came to her friendship with Elizabeth Glaser, who died of AIDS in 1994.

"Diana called my mom often in the last year of her life," Jake Glaser, Elizabeth's son, tells PEOPLE in this week's issue before World Aids Day on Dec. 1. "It was the love to support and protect their children that brought them together."

Elizabeth contracted HIV during an emergency blood transfusion after hemorrhaging while giving birth to daughter Ariel in 1981, two months after the first cases of AIDS were reported in the U.S. She unknowingly passed it on to her daughter Ariel through breast milk and then Jake, now 37, when he was born in 1984.

The wife of Starsky and Hutch actor Paul Michael Glaser, Elizabeth's battle made headlines when the family boldly came forward with their story in PEOPLE cover stories following Ariel's death at the age of 7 in 1988. The devastated mom channeled her heartbreak into action, creating the Elizabeth Glaser Pediatric AIDS Foundation (EGPAF) to fund research and stop the spread of the deadly disease. Her motivation to launch the foundation was to save her son's life.

"The strongest parallel between Princess Diana and my mother was definitely their love and advocacy for children," says Jake. "A mutual friend had introduced them, knowing that they would hit it off in this way."

EGAF Jake Glaser on Martha's Vineyard in 1994 with, from left, Paul, Elizabeth, Diana and Glaser family friend Ann Jordan

Jake says Diana and Elizabeth's connection kicked off with a "lengthy" phone call, and then they finally got to meet in person after the duo realized they were both going to be on Martha's Vineyard, Massachusetts, in August 1994.

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"My cousins have a house on Martha's Vineyard, and that was very much our safe space — our escape from the craziness of life, to go have fun and see our family," says Jake. "We invited Diana to the house and she came over."

"They really hit it off from moment one," says Jake, who adds that the moms bonded over having boys, Prince Harry and Jake, who are the same age. "She was there for her as a friend and supportive voice."

courtesy Jake Glaser Jake Glaser with his mom Elizabeth in 1992

The memory of that day is captured in a photograph of Diana, Elizabeth, Paul, Jake and Glaser family friend Ann Jordan.

For more on Jake Glaser's powerful journey, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.

"Even after that photo was taken," says Jake, Diana's calls to Elizabeth continued. Though Elizabeth's health began to fail that fall and she could no longer speak, someone would hold the phone to Elizabeth's ear so that she could hear Diana's words of encouragement, PEOPLE previously reported.

"Diana acted from the heart; Elizabeth did too," Paul, now 78, told PEOPLE in a story about their friendship that was published in 1997, following Diana's tragic death at the age of 36.

Elizabeth Glaser's 1991 cover of PEOPLE

Three years earlier, Elizabeth died at the age of 47 — but both her and Diana's passion for advocacy lives on in their children.

"Harry is his mother's son, as I am my mother's son. We're always looking for fun opportunities to continue supporting each other's work, both on the foundation side, but also as individuals," says Jake, who, as an ambassador for his mom's foundation, speaks to at-risk kids around the world, mentors HIV-positive youth in Africa and helps raise funds.

"We had a wonderful opportunity to spend some time together in Durban during the International AIDS Conference in 2016," he says of Harry. "It's not very often that you get to let down your hair and chat with a prince."

Diana's friend Elton John, himself a fierce HIV/AIDS advocate, also attended the conference alongside Elizabeth Taylor's grandchildren and Nelson Mandela's grandchildren.

EGPAF Jake Glaser (with fellow activists in Tanzania in 2017)

"It was a beautiful collection of individuals whose families have been a part of the fight against HIV and AIDS for the long haul," says Jake.

In recent years there's been some overlap between Harry and Jake's efforts in Africa, where each week nearly 2,000 children die of HIV/AIDS and roughly 9,000 more become infected with HIV. Sentebale, the charity that Harry co-founded in Lesotho and Botswana, partnered with EGPAF in Lesotho to "expand support for the provision of high-quality, comprehensive, evidence-based HIV and TB prevention, care, and treatment throughout four districts in Lesotho — with the goal of achieving and sustaining HIV epidemic control," according to an EGPAF spokesperson.

RELATED: Prince Harry Shares How His Mom Princess Diana, at 'Only 25 Years Old,' Fought Homophobia

With medical advances putting the foundation's goal of an AIDS-free generation within reach, Jake hopes to someday celebrate with Harry all the progress their mothers would be thrilled to see.

"Who knows what the future can hold?" says Jake. "We could have another picture of Harry and I on the vineyard, celebrating the eradication of HIV and AIDS one day."

To support work for an AIDS-free generation, visit pedaids.org.