Robin Roberts is a fighter.

The 51-year-old Good Morning America anchor updated her fans on her blog Tuesday about her battle with a rare blood and bone marrow disorder.

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"The start of last week went well but the daily chemo/treatment caught up to me by the weekend," Roberts wrote of her treatment for myelodysplastic syndrome. "My body is so weak but not my mind. You give me the courage to keep going."

"So today is my last day of chemo," she shared. "Wednesday is called a day of rest, yay, right! The transplant is scheduled for Thursday morning."

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After her mother, Lucimarian, passed away at the age of 88 on Aug. 30, Roberts delayed her treatment. The TV journalist left GMA a day earlier than planned to be by her ailing mother's side in Mississippi. 

"Last Sunday to lift my spirits I threw a little party at my apartment for my GMA family," Roberts, who beat breast cancer in 2008, blogged. "The next morning I walked through the hospital doors, with my guardian angels -- mom and dad -- back together and blazing a trail ahead of me."

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Roberts will receive the bone marrow transplant Thursday from her sister, Sally-Ann.

This article originally appeared on Robin Roberts on Pre-Transplant Chemo: My Mind Is Strong!