TMZ.com:  Court papers show that the Michael Jackson probate court authorized the estate to pay Michael's mom, Katherine Jackson, $26,804 per month.  Not bad for a granny raising three young uns.  Michael's three kids, however, are a little more high maintenance.  Katherine Jackson will be paid $720,000 per year for the kids expenses, including $159,120 a year for “entertainment and other.”

See also the LA Times story, “Jackson estate pays singer's mother $86,000 a month for expenses.”