Ashton Matheny loves being a new dad.
On a recent afternoon in Grand Forks, North Dakota, Ashton, 22, gave his baby girl, Haisley Jo, a bottle as he cradled the 4-month-old in his arms. He patted her on the back and put his face close to hers, and whispered, “Hi,” and when she flashed him an adoring smile in return, he lit up.
“She’s a Daddy’s girl,” he says.
But what should be the happiest time of Ashton’s life is marred by tragedy: In August, Ashton’s longtime girlfriend, Savanna LaFontaine-Greywind, 22, who was eight months pregnant with their first child, was murdered for her baby, say authorities, leaving Ashton to care for Haisley Jo alone.
“Now,” he tells PEOPLE. “I’m mom and dad.”
Five days after Savanna vanished on Aug. 19, Fargo police found her neighbor, Brooke Lynn Crews, 38, with the young couple’s newborn in her third-floor apartment, located in the same building where Savanna lived with her family.
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On Aug. 24, Crews and her live-in boyfriend, William Henry Hoehn, 32, were arrested and charged with conspiracy to commit murder, conspiracy to commit kidnapping, and giving false information to the police.
Three days later, Savanna’s body was found in the nearby Red River, wrapped in plastic. Autopsy results revealed that she died of “homicidal violence.” Authorities have not yet specified how or where Savanna died or how the baby was born.
While still grappling with the trauma of losing Savanna, Ashton focuses on caring for Haisley Jo. His days are spent bathing, feeding and changing her, trying to get enough sleep and making sure he doesn’t forget any of her baby gear when they go out.
“I have to go over a checklist every time I leave the house,” he says.
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Crews pleaded guilty to the charges against her on Dec. 11 and will be sentenced on Jan. 16. Hoehn pleaded not guilty in September and is awaiting a March trial. They each face life in prison without parole.
While Hoehn’s attorney did not return calls for comment, Crews’ attorney says he hopes his client’s guilty pleas will help her get a lighter sentence.
In the meantime, Ashton carries on without the woman he planned to marry. “She would have been the best mom ever,” he says. “She was so good with kids.”
A GoFundMe account has been set up to help Haisley Jo and Ashton with expenses.