Paris Jackson is demanding to speak directly with her grandmother Katherine Jackson, who has left Los Angeles to stay with her daughter Rebbie in Arizona.
The mother of late pop icon Michael Jackson was reported missing by nephew Trent Jackson over the weekend although the state's Pima County Sheriff's Department said she was safe and well when they visited her.
However Michael's 14-year-old daughter is still worried about her relative.
She tweeted: "8 days and counting . something is really off , this isn't like her at all .. i wanna talk directly to my grandmother!!< 3."
Her cousin TJ Jackson replied: "I know it's completely unfair for them to do this to you and your brothers. We will keep trying. I love you."
Jermaine, Randy and Janet Jackson have been barred from their mother's Calabasas, California home after allegedly attempting to remove their brother Michael's three children from the house.
A source told website RadarOnline: "Randy was telling Prince Michael he had to leave with them and that he had a private jet chartered to take them all to Arizona to see Katherine. Prince firmly held his ground and told Randy he wasn't going anywhere with them."
The unusual situation comes after 82-year-old Katherine's children, also including Tito, wrote a letter demanding the resignations of the executors of Michael's estate because they believe his will was a fake.
The letter also alleged that the executors' manipulations left Katherine in bad health and caused her to have a mini-stroke which she has denied.
Michael died in 2009 when he overdosed on prescription drug Propofol.