The sudden passing of Mark Sheehan, the guitarist of Irish pop band The Script, at age 46 has left fans seeking answers about the cause of his death. Sheehan died after a "brief" illness, according to a social media post by the band, which described him as a loving husband, father, brother, bandmate, and friend.

Sheehan is survived by his wife of 17 years and their three children. While there is no official information on his cause of death, the mention of a brief illness has led to speculation that cancer may have been involved. Prior to his passing, there were no reports of Sheehan having cancer or any other serious illness.

In light of Sheehan's relatively young age, fans have expressed their shock and sorrow over his untimely death, with many offering condolences to his family. Last year, Sheehan took a break from The Script's US tour, which, in retrospect, may have been related to his illness. At the time, lead singer Danny O'Donoghue explained that Sheehan had taken time off to be with his family, stating, "It's his story to tell, but yeah, I guess if I could paraphrase, his children needed a father and his wife needed a husband."

More details on Sheehan's cause of death may emerge as further information comes to light. Sheehan was a talented musician, co-founding The Script in 2001 with childhood friend Danny O'Donoghue and drummer Glen Power. The band achieved great success with hits such as "Breakeven," "The Man Who Can't Be Moved," and "Hall of Fame," selling over 20 million records worldwide.

Sheehan's contributions to the band's music were highly regarded by fans and critics alike. His death represents a significant loss to the music industry. Before forming The Script, Sheehan was a member of the boyband Mytown, which was managed by Eamonn Maguire and signed to Universal Records in New York. Sheehan and O'Donoghue also produced two tracks for Peter André's album "The Long Road Back" under the name M.A.D Notes before launching their careers as musicians.

Sony Music, The Script's label, paid tribute to Sheehan on Twitter, writing, "We are deeply saddened by the tragic loss of Mark Sheehan - a hugely talented songwriter, guitarist and founder member of The Script, one of Ireland's greatest bands. Our thoughts are with his family, fellow band members and fans at this time."

Celebrities like former Love Island presenter Laura Whitmore and fellow Irish musician Hozier have also expressed their condolences on social media.