Katherine Jackson does not asked the Estate to pay for Janet Jackson's mortgage

Katherine Jackson's request for the Michael Jackson Estate to pay for expenses related to Janet Jackson's Las Vegas home are not for mortgages.

The Estate filed documents asking the court to allow the Executors to pay Katherine for "expenses relating to a residence in Las Vegas."

TMZ was told the residence is Janet Jackson's home and there's no need to cover any mortgage expenses, because Janet doesn't have a mortgage -- she owns the home outright, but never spends time there. In fact, she bought the home so Katherine could use it.  And, she has provided various other forms of support for Katherine over the years.  So what TMZ reported initially -- that the Estate would pay part of the mortgage -- isn't the case.

Sources connected to Katherine now tell us, Katherine wants the money because she incurs various expenses when she spends time at Janet's property.  TMZ sources say the expenses include, food, cable, utilities, Internet, travel and even toilet paper.   

It's unclear why Katherine feels she's entitled to more money for things like food and toilet paper, because what she consumes and uses in Vegas she doesn't in L.A.