The newborn daughter of "Big Brother" fan favorite Britney Haynes was diagnosed with cancer on Sept. 1.

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The "Big Brother 12" alumni welcomed her first child with husband Ryan Godwin on July 13, announcing on Twitter that Tilly Elizabeth was "happy, healthy, and amazing" at 8 pounds, 3 ounces.

Now, the joyous occasion has taken a tragic turn, as Haynes has revealed on Facebook that her daughter is suffering from an unspecified form of cancer.

Her post reads, "On September 1st, we were among the daily 720 sets of parents to be absolutely devastated with a Childhood Cancer diagnosis... Please take time to pray for all these children, our sweet baby included."

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