Winter Haven police say they arrested Christopher Scott Ryon, 27, of Polk County, after Riley Ryon's mother, Kristine Bardell, 26, found the child lying face down and unresponsive in their apartment bedroom when she came home for lunch Tuesday about 1:15 p.m., the Orlando Sentinel reported.
It was unclear whether Ryon and Bardell are married.
Bardell called emergency responders who attempted, unsuccessfully, to resuscitate the infant while they transported her to Winter Haven Hospital, where she was pronounced dead, WFTS-TV, Tampa, Fla., reported.
The District 10 Medical Examiner's Office conducted an autopsy on the baby, concluding she had a skull fracture indicative of a blunt force trauma.
"He wanted to take a nap,'' police said in a statement about Ryon's alleged motive for punching his daughter.
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