(Photo Courtesy TLC)

She lives her life on camera, but TLC TV personality Jen Arnold has been fighting a private battle too.

The "Little Couple" star has cancer, she revealed to ABC News.

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"I have recently been diagnosed with a rare type of cancer and am currently undergoing treatment, including surgery and chemotherapy," she said in a statement, which was first reported by People. "I am very fortunate as the prognosis is very good." She did not specify what kind of cancer she has.

Arnold, 39, and her husband Bill Klein, 38, have a son Will, 3, whom they adopted from China and a 2-year-old daughter Zoey, whom they recently adopted from India. The family lives in Houston, where Arnold works as a neonatologist and Klein runs a store, Rocky and Maggie's Pet Shop.

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"While there is never a good time to get news like this; getting it just as we are building our new family is tough in many ways,," Arnold continued, "but being surrounded by the love of my husband and our two beautiful children is actually in many ways giving me the strength to fight it even stronger."