What is scleroderma, the disease Bob Saget fought for during his life?

The star, who died suddenly on Sunday, supported the Scleroderma Research Foundation for decades

Bob Saget dead at 65.

Following the death of “America’s favorite dad,” Bob Saget, 65, on Sunday, many close to him suggested that a donation to the Scleroderma Research Foundation, a cause close to his heart, would be a fitting tribute. But what exactly is scleroderma and why did Saget support the foundation?

Saget first became a supporter of the non-profit in 1991, and became an outspoken advocate after his sister Gay was diagnosed with the rare autoimmune disease, according to the foundation.

“My sister, Gay Saget, was a school teacher near Philadelphia. She was 44 when she was diagnosed with systemic scleroderma. She passed away just two years later,” he told “NIH Medline Plus Magazine” in 2019.

Scleroderma is a rare, autoimmune connective tissue and rheumatic disease that primarily causes skin inflammation but can progress to other parts of the body, according to the National Institutes of Health.

In mild cases, scleroderma only affects the skin. However, in severe cases, known as systemic scleroderma, the disease spreads throughout the body and “can damage your blood vessels and internal organs, such as the heart, lungs and kidneys,” NIH states on its website.

On Monday, the organization issued a statement on Saget’s death.

“It is with a very heavy heart that we mourn the loss of our friend and Board member, Bob Saget,” the organization said. “Bob was a champion for scleroderma patients everywhere dating back to 1991 when he first became involved with the Scleroderma Research Foundation (SRF), even before his sister Gay lost her battle with the disease in 1994. Bob was a deeply caring father, husband, and colleague, who was unreservedly committed to the mission of the SRF.”

In addition to his many other contributions to the non-profit, Saget directed and produced a TV movie, “For Hope,” loosely based on his sister’s battle with scleroderma, which continues to raise awareness of the disease, the organization added.

In a May 2021 Instagram post, the “Full House” star said that it was “one of my life’s missions to help find a cure for this disease.”