Splash News 1 / 26

Kurt Cobain's 1959 Martin 18-DE electric/acoustic guitar remains at the center of the increasingly heated divorce battle between Frances Bean Cobain and her ex, Isaiah Silva.

This week, TMZ reported Frances asked a judge handling their case to force Isaiah to give up the guitar, which he said last summer he intended to keep because he believed Frances gave it to him as a gift after their 2014 wedding.

Frances and her mom, Courtney Love, disagree with Isaiah about who owns the instrument.

"It's not his," Courtney told TMZ last year. "It's a treasured heirloom of the family's." She added that it was never her daughter's intention to let Isaiah keep the guitar, which Kurt used in his iconic Nirvana "Unplugged" performance and is believed to have been the last guitar he played before his death in April 1994.

In court documents, Frances asked the judge to have Isaiah return the guitar to her so she could inspect it and make sure it's in the same condition it was when she last saw. She then wants it to be sent "to an art shipping company for safekeeping," according to TMZ.

In the meantime, Frances is making waves in the fashion world, where her first image from Marc Jacobs' Spring/Summer 2017 campaign appeared on the designer's Instagram on Wednesday, Jan. 25.

In the photo's caption, Marc explained that he's known the 24-year-old since she was just 2 years old.

"I have always wanted to work with Frances. Her beauty, uniqueness, and strength is something I have long admired and respected," he wrote.

Speaking to Vogue, Frances admitted she doesn't always say "yes" to modeling offers.

"I don't model unless I think the project is cool, and I don't put my name behind something that I don't genuinely believe in. I thought this collection was great, and I was flattered that Marc thought of me for this," she said.

"I could never do (modeling) professionally, but I'm glad I did it with Marc, because I trust him."

Frances filed for divorce from Isaiah in March 2016. In the filing, she said she'd pay spousal support to the musician but noted he should not be granted access to any of the money left in her father's estate, which is estimated to be worth hundreds of dollars.

The guitar is one of 300 like it ever made, according to Esquire, and is worth millions.