A three-year-old girl is in the hospital after she and her twin sister fell from the second-story window of their family's home in the Germantown area of Philadelphia Saturday.

The incident occurred around 12:30 p.m. on the 500 block of Manheim Street. Family members identified the girls as Madison and McKenzie Whitney, according to 6ABC.

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Madison suffered a fractured skull and was rushed to St. Christopher's Hospital for Children, where she is listed in fair condition. No injuries were reported for McKenzie. 

Family members said they think Madison broke McKenzie's fall.

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Police said the girls likely fell 20 to 30 feet into the family's backyard.

"They were supposed to be taking a nap. I put them down for nap. I went and checked on them," Rob Whitney, father, told 6ABC. "The next thing I know, I'm getting told one of them is outside."