A heartfelt letter Michael Jackson sent to a father-figure security guard has hit the auction block.

The handwritten note addressed to his personal security guard, Bill Bray, is expected to fetch as much as $18,000 (£13,700).

The letter, written in the early 1990s, went on sale on Thursday (07Mar19) via RR Auctions and bidding will continue until 14 March.

In it, Michael tells Bill he loves him and admits, "I don't know what would have happened to me if you were not around", thanking his longtime security guard for "being a father" to him.

Bray started working security for the Jackson 5 in the 1970s and stayed by Michael's side until his retirement in the mid-1990s, according to RR Auction bosses.

The auction news comes as members of the Jackson family and officials overseeing the late King of Pop's estate battle child molestation allegations detailed in damning new documentary Leaving Neverland, which debuted in America over the weekend and screened in the U.K. on Wednesday night.

RR Auctions bosses are also selling off the hospital gown Kurt Cobain wore for his final British performance at the 1992 Reading Festival.

The Nirvana frontman hit the stage in a wheelchair pushed by journalist pal Everett True as he poked fun at reports he was near death.

The gown is expected to fetch more than $52,000 (£40,000).

"This iconic and museum-quality piece represents the Nirvana frontman at his finest and most sardonic, jabbing pointedly at critics and detractors alike while retaining the intensely original showmanship that made him a living legend," auction house bosses said.

After Cobain’s death in 1994, his widow Courtney Love reportedly gave the gown to a fan who had attended a vigil in his memory. The fan kept hold of the precious item for 25 years, before putting it up for sale.