Jahi McMath, 13, was declared brain dead in December. (Courtesy of McMath Family and Omari Sealey/AP Photo)

Weeks after a brain-dead 13-year-old girl was moved to an undisclosed facility following a legal fight between the girl's family and hospital, her mother is speaking out about their experience and says she has "hope" for her daughter.

Nailah Wakfield, who fought to keep her brain-dead daughter Jahi McMath on life support, posted a letter on Facebook to thank supporters and to give an update on her daughter's condition.

Jahi, 13, was declared brain-dead after temporarily going into cardiac arrest due to complications from having a surgery on her tonsils and adenoids. She was declared brain dead on Dec. 12 by multiple doctors after extensive testing. For weeks her family fought to keep her on life support, but the Children's Hospital of Oakland, which treated Jahi, no longer wanted to treat her by keeping her on the machines.

Eventually the family managed to find an undisclosed facility that would take Jahi and the girl was moved after being given a feeding tube. Jahi has been declared medically dead by at least three different doctors.

Wakfield wrote a letter on Tuesday about why she had kept silent, saying she did so in part for "safety and privacy," and so she could focus on her role as a "mother." Wakfield further said that she had "hope" after her daughter was moved to the new facility.

"I can tell you that she is much better physically since she has left Children's Hospital and I see changes that give me hope," Wakfield said.

She did not elaborate on the changes.

Wakfield also thanked those who had shared similar stories and even the people in the public eye who debated the case and gave it attention.

"I also want to thank those who felt the need to go public with their opinions about me and my daughter, positive and even negative," said Wakfield. "It is because of you that my daughter's experience is so relevant and that people all over the world know who Jahi McMath is."

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