Peter Yarrow, the singer-songwriter who formed one third of the folk trio Peter, Paul and Mary, has died at the age of 86, his representative confirmed to ABC News.

According to the representative, Yarrow died of bladder cancer. The singer had been battling the disease for several years, a journey he and his family documented on Yarrow’s official website.

“So grateful for all the love and support from extended family, dearest friends and everyone who wrote living tributes, sent prayers and sang songs that connect us with peace as a song in our hearts,” Yarrow’s daughter Bethany wrote on the website four days ago, along with an undated photo of Yarrow in bed. “Peter is physically very weak, but his spirit is strong and his light grows brighter every day. We won’t let the lights go out! We love you, Peter!”

Yarrow began performing as Peter, Paul and Mary in 1961 alongside Paul Stookey and Mary Travers and made a name for himself by appearing in New York nightclubs and coffeehouses. Their self-titled debut album, released a year later, reached the top of the Billboard album charts and included the hit singles “Lemon Tree” and a cover of the Pete Seeger standard “If I Had a Hammer (The Hammer Song).”

Perhaps Yarrow’s most enduring song with the trio was “Puff the Magic Dragon,” which he wrote based on a poem by the then 19-year-old author and filmmaker Lenny Lipton. Although some said at the time that the quirky song was about marijuana use, Yarrow claimed it was an ode to leaving childhood behind when growing up.

The 1964 single peaked at No. 2 on the Billboard Hot 100 singles chart and has been covered countless times since. It also inspired three animated television films as well as a 2007 book by Yarrow and Lipton.

The trio’s biggest hit, however, was the 1969 recording of “Leaving on a Jet Plane”, written by the then largely unknown John Denver. The single was Peter, Paul and Mary’s only No. 1 hit in the US and their last Top 40 song before they disbanded in 1970.

Also in 1970, Yarrow pleaded guilty to taking “inappropriate and immoral liberties” with a 14-year-old female fan the year before and was sentenced to one to three years in prison, of which he served three months. In 1981, he was pardoned by President Jimmy Carter shortly before he left office.

Yarrow also co-wrote the 1976 Mary MacGregor No. 1 hit “Torn Between Two Lovers.”

Peter, Paul and Mary reformed in 1981 and continued to perform until Mary Travers died of complications from leukemia in 2009. Yarrow and Stookey continued to perform as solo artists afterward, with Yarrow frequently performing with his daughter Bethany and remaining active in the folk music scene until his illness made it difficult for him to continue.

After Yarrow’s death, only Paul Stookey remains of the trio.