Family sources tell TMZ ... Mama June is currently in custody of Anna's 11-year-old daughter Kaitlyn.
Anna, who died Saturday after a difficult battle with cancer, had 2 daughters with 2 different men ... and our sources say the younger child, 8-year-old Kylee, is now living with her biological father, Michael.
We're told the family had a plan in place for Kylee to move in with her dad should something happen to Anna, who was diagnosed, back in January, with stage 4 cancer.
Our sources say Kaitlyn and Mama June have a very close bond -- she's June's first grandchild -- so, everyone in the family agrees, moving her to Grandma's house is the best situation for her. We're also told June plans to become Kaitlyn's legal guardian.