"Demi has moved in, and she is not leaving until the very end," spilled the source, who noted the 60-year-old Ghost actress also stayed with Bruce's bunch during the pandemic.
"At first no one outside the family could understand what Demi was doing living with her ex and his new wife, but now it makes sense," charged the insider. "Demi has been a rock for the family and is determined to make sure every day Bruce has left on earth will be filled with love."
While a rep insisted Demi hasn't gone all in on the unusual living arrangement, another source insisted the actress "never left" after the pandemic nesting.
"Now Bruce will leave before she does," said the source of the 68-year-old star's struggle with his diagnosis of frontotemporal dementia, for which there is no known cure.
RadarOnline.com has reached out to Demi's team for comment.
As this outlet reported, Bruce's ex and his current wife have only gotten closer as his health continues to deteriorate.
"Demi has been in constant contact with Bruce and Emma," a source revealed earlier this year. "She's taking every opportunity she can to spend time with him."
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The entire family has been rallying around the legendary action hero.
"They know he won't be around forever," another insider shared. "So they're cherishing every single moment."
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They are holding onto hope for a miracle — especially now that Rumer is pregnant with his first grandchild.
"He's determined to stay coherent and lucid for as long as possible so his grandchild can have some happy memories of a grandfather who was present and active in his or her life," a friend revealed last month. "He's dead-set that this new baby is going to get the best he has to offer."
Bruce's health decline has been the hardest for his oldest children to watch.
"It's been painful to see him deteriorate," said the source. "The older girls miss the old Bruce — the one who used to tease them about their boyfriends and give them unsolicited advice."