A high school teacher in Ohio allegedly gave birth to her pupil's baby after grooming him from the age of 14.
Laura Lynn Cross, 36, has been accused of sexually abusing the teen over a three-year period, from August 2013 until last September.
At one point she even posed as his "mentor" to gain joint custody so he could move into her home, where they were allegedly having sex.
The pupil's father said he first raised concerns with police and officials at Buchtel High School, Akron, where Cross taught, in 2012.
He believed their relationship had become too close, but no charges were filed.
"First of all, she's just a school teacher – to get aroused by a child you have to be a sick individual," he told ABC News 5.
"I was told by the school that she had a 'hold' on him and he was not cooperating, so basically they can't do nothing with it."
The boy's father told of how Cross allegedly first began to groom his son by making requests to go "swimming in the pool" with the teen. She then asked whether he could spend the night at her home in the nearby suburb of Tallmadge.
The case became more disturbing when she convinced the teen's mother, who had custody, to allow the youngster to move into her home through a court-approved "partial parental custody" arrangement.
Cross said it would allow her to "mentor" her pupil more effectively.
Charges of three counts of sexual battery were only brought against Cross earlier this month when police learned that she had given birth to the teen's baby in 2015, the same year she resigned from her teaching post.
"It was a straight failure from the system, from the school and definitely from the police," said the teen's father, who only discovered he was a grandfather when a tipster called him in May.
A spokesperson for the Akron School System, which oversees Buchtel High School, says the district was unaware of the case until it was reported in the media.
It said it is now "doing our own internal investigation going back to 2012 to determine what exactly happened and when it happened".
Cross is currently being held in the Summit County Jail under $100,000 bond.
A pre-trial hearing is scheduled for 31 August.