The showbiz matriarch - who temporarily lost custody of late son Michael's kids Prince, 15, Paris, 14, and Blanket, 10, when she made an unexpected trip to a spa in Arizona - is unwilling to meet with Janet, Randy and Rebbie Jackson because she believes they misled her and didn't tell her that her grandchildren had been trying to contact her during her stint away from California.
The siblings are reportedly banned from entering the home in Calabasas where Katherine lives with her grandchildren because they are at war with the executors of Michael's estate - which pays for the property - but their mother is said to be "heartbroken" over their recent behaviour and doesn't want to see them.
A source said: "For the time being, Janet, Rebbie, and Randy aren't allowed at the home. The executors were asked to send a letter to Katherine's children after the trio, plus Jermaine, descended onto the house while Katherine was in Tucson, Arizona unaware that her grandchildren had been trying to reach her, and an altercation ensued.
"Katherine is free to see Janet, Rebbie or Randy, just not at that house. However, Katherine has absolutely no desire to see them right now because she is just heartbroken that they betrayed her trust and didn't tell her that Michael's children had been trying to contact her."
The problems began when Janet, Rebbie, Randy and their brothers Jermaine and Tito sent a letter to Michael's estate executors John Branca and John McClain demanding their resignation. However, Jermaine and Tito later released statements in which they said they regretted signing the document.
Katherine - who is now temporarily sharing guardianship of Michael's children with her grandson TJ Jackson - is said to be particularly unhappy with Randy's conduct during the family's difficulties.
The source added to RadarOnline.com: Katherine Jackson will "never publicly say anything negative about her children, it's just not who she is. However, she is just absolutely disappointed that Janet, Randy, Rebbie, and Jermaine would keep her in the dark like that. Jermaine has apologised, but Katherine can't forget it.
"Katherine recognises that Randy was behind all of this, and wishes he would stop spouting off to the press about their family business. She isn't having any contact with him especially right now."
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