Progressive country songwriter and producer Busbee has died. The well-regarded hitmaker had written hits for many of the most influential artists of the last five years, most notably Maren Morris and Keith Urban.

News of Busbee's (real name: Michael James Ryan) death at the age of 43 started to spread on social media late Sunday night (Sept. 29). Pop singer and songwriter Ross Golan and Morris confirmed the news in tweets.

He is survived by a wife and three children, according to PeopleCMT reports that he had been diagnosed with a rare brain cancer called glioblastoma a few months ago.

A repertoire search at the BMI website shows more than 1,000 songwriting credits to Busbee's name. Florida Georgia Line, Rascal Flatts and Lady Antebellum are three more country artists he worked with extensively.

Busbee lived behind the scenes, even by usual songwriter standards. A Rolling Stone article from 2016 is one of very few extensive pieces on his life and music available. He came from Los Angeles and a jazz background before he started writing songs for pop and country audiences more than a decade ago. While he found success on country radio as far back as 2011 with Hunter Hayes' breakthrough hit "Storm Warning," it was the songs on Morris' Hero album ("My Church," "'80s Mercedes," "Once") and Urban's Ripcord album ("Sun Don't Let Me Down," "The Fighter," "Your Body") that caught all of Nashville's attention.

Keith Urban Recalls How Busbee Saved His Song "The Fighter"

FGL's "H.O.L.Y." and Garth Brooks' "People Loving People" are two of his other early credits. His fingerprints could be found all over 2017 albums from Carly Pearce and Lady Antebellum. He also co-produced albums from Lauren Alaina and both of Morris' studio projects.

Pearce shared a particularly emotional Instagram note after learning of his death. Busbee helped her write her breakthrough hit "Every Little Thing."

"You gave my music a place in this world," she says. "I’ll cherish the 2 albums, songs, talks, laughs & memories we shared over the years. My heart is broken, but the legacy of your talents and your heart will live on in all of the artists and people you touched. I love you, Busbee."

Blake Shelton also tweeted about Busbee's death on Monday morning, speaking to the songwriter's pop influence, as well. He had worked with and written songs for Gwen Stefani, Katy Perry and Pink plus many more.

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