Glen Campbell's Alzheimer's Battle: Inside the Country Star's Good and Bad Days at His Memory-Care Community

Four years after being diagnosed with Alzheimer’s, Glen Campbell rarely recognizes his loved ones and can no longer play music or carry a conversation, but the country legend is still very much Glen Campbell.

“He still has the same essence. He still has the same twinkle in his eye. He has the same chuckle, and he’s still an entertainer,” his wife of nearly 33 years, Kim Campbell, tells PEOPLE.

Living full-time at a Nashville memory-care facility located minutes from the Campbell’s home, Glen, 79, is cared for by a family friend and personal sitter named Brody, but his main caregiver is still Kim, who visits him daily.

“We’ll split shifts a lot of times,” explains Kim, 57. “He’ll go for lunch and do some activities with him and I usually do the afternoon, dinner and stay with him until he goes to bed.”

The couple’s children Ashley and Shannon (their son Cal lives in California) also visit with their dad, and often play music for him. Says Shannon: “I like to play him his old songs. It seems like he likes to fall asleep to that.”

According to musician Carl Jackson, Glen’s longtime collaborator and friend who introduced him to Kim, the star “still has that humor inside of him,” he says. “Every now and then, he’ll go into his Donald Duck voice. Occasionally he’ll still have an ‘I love you’ and ‘That’s my sweetie.’ The gleam in his eye is still there.”

Glen has five other children from previous marriages; two of his oldest children, Debby Campbell-Cloyd and Travis unsuccessfully bid for control of his affairs earlier this year.

During her twice-a-month visits, “he reaches out to me and hugs me and say, ‘Oh, my baby girl,’ ” says Debby. “It’ll go away and it’ll come back, [but] if I hear it five to six times when I’m there, I’m good because it means he came to me at that moment.”

Things that make him happiest are “hugs and a vanilla bean frappuccino,” says Ashley. “His face lights up. I’ll usually bring one when I come visit, and if he’s zoning out, I’ll get the straw near his mouth, he’ll take a drink and immediately it’s like coming to life.”

The family is also focused on continuing Glen’s work of raising awareness of Alzheimer’s through his documentary Glen Campbell: I’ll Be Me (airing Sunday at 9 p.m. on CNN, with a digital download available beginning Aug. 18 and out on DVD Sept. 1), which followed the singer and his family on his 2011 tour as his memory declined.

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“I’m very grateful that he turned something horrible into something with great meaning,” Ashley says about her dad, who went on to record two albums and play more than 150 shows on tour after his diagnosis. Adds Shannon: “He didn’t let it get him down and he was always happy to be there.”

For Kim, who admits she suffers from depression, knowing she’s able to help other families going through similar situations is what keeps her positive.

“We just try to stay focused on Glen, loving him and taking care of him,” she says. “Glen’s done so much good, and the focus needs to be on what a wonderful man he is and what great things he’s done for other people who have Alzheimer’s.”

For much more on Glen Campbell’s life now and how his family is dealing with the devastating disease, pick up the latest issue of PEOPLE, on newsstands Friday

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