A 10-year-old girl shot in the buttocks by a stray bullet was given a sanitary towel and told to go back to sleep by her parents, who thought the blood was coming from her first period.
The girl's parents - who have not been identified - told police they did not report the shooting for more than five hours after the injury occurred, adding that they never reported the sounds of gunshots if they heard them outside their California home.
The girl was shot once in the buttocks around 2am on Thursday evening and remained hospitalised in a stable condition until Friday, Hayward Police's Lt Mark Stuart told the San Jose Mercury News.
"They said they heard a popping noise, but didn't know they were gunshots," Stuart said of the parents' account. "So they didn't know their daughter was shot because they did not go into her room."
The girl told her mother and older sister that she "felt a pain and burning sensation in her lower extremities," Stuart said.
He described blood on her clothing, and said the family had examined her in the bathroom and concluded she had begun her period.
"An older sister gave her a pad and told her to put it on and go back to bed," Stuart said.
It was only when the girl woke up for school the next morning that her parents found the bullet wound, and noticed bullet holes by her bed in the front bedroom.
Stuart added: "The doctor said that if that's what they were seeing and they never initially saw the entry wound from behind, that it's plausible to believe it was a period as opposed to being shot."
Police investigations continue, but the parents will not be probed on suspicion of child neglect.