MARIE OSMOND battling her ex-husband in an ugly stand-off over the last wishes of her late son, Michael,  who committed suicide last year.

The beloved entertainer – who recentrly re-wed first hubby Stephen Craig – is locked in a battle with ex-husband Brian Blosil over which last name to put on their adopted son Michael’s head­stone.

A year after his sui­cide at age 18, Michael still doesn’t have a proper monument at a cemetery in Provo, Utah.

“Brian and Marie are still deal­ing with the fallout from their nasty 2007 divorce, and can’t come to terms on the name on Michael’s stone,” explained an insider.

Michael – who leaped to his death from his eighth-floor Los Angeles apartment in February 2010 – despised his father and was in the process of changing his last name from Blosil to Bryan, say sources.

Since Michael died without a will, both Marie and Brian have control over his estate.

“She knew Michael hated Brian. He felt Brian had emotion­ally and physically abused family members.”

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