She is asking the court to appoint her as the guardian for all three kids.
The petition states the kids have "no relationship with their biological mother."
According to the petition, the kids are in the care of Katherine and they have "a long established relationship."
The petition says the value of Michael Jackson's assets are unknown at this time.
Debbie Rowe is named as mother of two children in the petition.
As for why Katherine thinks it would be "best" to appoint her guardian, "Minor children are currently residing with paternal grandmother. They have a long-established relationship with paternal grandmother and are comfortable in her care."
The petition says it's "not known at this time" whether the mother (Rowe) agrees that Katherine should be the legal guardian.
As for Prince "Blanket" Michael Jackson II -- MJ's third child -- the box where it says "mother" is checked "none." The DOB is listed as January 21, 2002.
A hearing is now set for August 3 to hear the petition.