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Today was Robin Roberts last day on Good Morning America before she embarked on a treatment journey to combat her Myelodysplastic Syndrome diagnosis, and it was just revealed that some A-list stars will be keeping Robin's seat warm over the coming weeks.

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Oprah Winfrey, Chris Rock, Rob Lowe and the cast of Modern Family will join Diane Sawyer, Katie Couric, Barbara Walters and Kelly Ripa in co-hosting the 8 a.m. hour throughout Roberts' treatment.

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"This means so much [that] these friends are stepping up like this," Roberts said. "I love them for that!"

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