"I gave them his complete medical records from his physical examination to his lab work," Lee, a registered nurse, said Wednesday, of the subpoena for her records.
The Jackson family has said from the start that they were suspicious of its most famous member's death. Joe Jackson told ABC News earlier this month that he thinks his son was the victim of "foul play," and La Toya Jackson went so far as to tell British tabloids that she believed her brother was murdered.
Jackson's three children remain in the temporary custody of his 79-year-old mother, Katherine Jackson. A custody hearing has been postponed twice as she and Jackson's ex-wife Debbie Rowe reportedly negotiate an agreement.
Rowe is the mother of Jackson's two oldest children, Prince Michael I, 12, and Paris-Michael Katherine, 11. The youngest child, Prince Michael II, 7, also known as Blanket, was born to an unnamed surrogate.
TMZ reported overnight that even if Katherine gets custody, the children will likely be raised by Jackson's eldest sibling, Rebbie Jackson, 59, who has been very involved in the children's lives.
ABC News' Michael S. James and Lauren Pearle contributed to this report.