The singer-songwriter was admitted to the Nashville, Tennessee medical centre in early 2014, after Kim, his wife of 33 years, decided it was time to seek professional help for her ailing husband - but now she's his primary care-giver again as he battles the sixth of seven stages of Alzheimer's disease.

She tells the Chattanooga Times Free Press Campbell quietly returned home in late July (15), and it's sometimes tough to be around the confused country star.

She says, "He can become extremely combative if you try to redirect him to something that he doesn't want to do. I have a black eye right now. I know that's not him, that's not who he is; it's just the Alzheimer's."

But Kim insists their time together is not always challenging, adding, "He calls me Mrs. Campbell... He definitely understands smiles, hugs, kisses. He's physically healthy, cheerful and content most of the time."

Earlier this year, two of Campbell's children, Debby Campbell-Cloyd and Travis Campbell, launched a legal battle against Kim, accusing her of "secluding" their dad "from the rest of the family".

In a petition, filed in March (15), they urged a judge to appoint conservators and a guardian to protect their father's medical and financial interests.

Debby is the singer's daughter from his first marriage to Diane Kirk, and Travis is his son from his second union, with Billie Jean Nunley.