Demi Lovato’s ailing father has a heartbreaking message for his estranged daughter: please call me.

Patrick Lovato exclusively told RadarOnline.com that he has been desperately trying to reach his 19-year-old Disney star daughter, but so far to no avail.

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Demi Lovato will be spending the upcoming Thanksgiving holiday at her treatment facility.

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The singer and actress, who has been at the facility for over two weeks, will be joined by her family.

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They will be there “to celebrate” with Lovato, her rep told People.

The rep added:  "She remains committed first and foremost to her treatment. Demi has made tremendous progress to date, but understands that she has more work to do."

Demi Lovato is in her second week at a treatment center working on “emotional and physical issues” and is doing well according to her father Patrick Lovato, who recently spoke to the young star over the phone.

In an exclusive interview with RadarOnline.com, Patrick said: “Demi’s doing great, she’s such a strong girl.”

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Patrick said Demi called him this week and they spoke about his cancer. “She told me she loved me, she really loves her daddy,” he said.

“She told me she’s getting better.”

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