Detectives with the Buchanan County Sheriff's Department said it happened around 2:30 A.M. on December 18th.
They wouldn't share the exact address of the home because they didn't want to identify the victims but said a couple and their adult daughter were home at the time.
The news has some neighbors on edge.
"It's just sick that somebody would go in during the holidays and do something like this," said Zachary Papereert.
The young woman told authorities a man sexually assaulted her while her parents were sleep.
The man took several items from the home, including a debit card.
Authorities say he used the card to pay for gas in Percival, Iowa.
The Sheriff's Department released photos of the man they consider a suspect in the case.
He's described as being between 5'2 and 5'6 in his late 30's or 40's and wearing a blue and red cap with glasses.
Detective Mike Wilkerson hopes the photos will help track down a suspect and learn more about what happened that night.
"This particular incident I don't think the people could have done anything differently, it was just an unfortunate act that occurred and now we're trying to identify the suspects involved in this case," says Detective Wilkerson.
He says the suspect broke into the home but reminds people to always check their surroundings.
"Make sure your residence is locked up, make sure if you have neighbors,you tell your neighbors that you're going out of town so they can keep a look out," added Wilkerson.
Authorities also say the man was driving a light-colored vehicle and they believe others might have been involved.