Savanna LaFontaine-Greywind
The body of Savanna LaFontaine-Greywind, 22, was found in a river on Sunday (27 August) Police handout

US authorities have finally allowed the boyfriend of a pregnant North Dakota woman and her family members to see the baby they believe to be hers after her death.

Savanna LaFontaine-Greywind was eight months pregnant when she went missing on 19 August. Her body was found after an eight-day-long search in Red River on Sunday (27 August), wrapped in plastic and trapped by a log.

After holding the newborn in his arms, Matheny, LaFontaine-Greywind's boyfriend said: "It was the best feeling I've ever had. I wish Savanna could have been there to enjoy it with me. After all these dark days, she lit my day right up."

"She's my miracle baby. She was perfect coming in," he added.

The baby has been kept under the care of Cass County Social Services until a DNA test proves that she is LaFontaine-Greywind's and Matheny's child. Police are also investigating whether the child was removed from the woman's womb, before or after her death, the BBC reported.

The development came two days after a couple was charged over allegations that they killed LaFontaine-Greywind to claim her baby as their own.

William Henry Hoehn, 32, and 38-year-old Brooke Lynn Crews were held after the two-day-old baby was found in their apartment.

Authorities have told local media that Lafontaine-Greywind disappeared after going to the couple's apartment to help with a sewing project, but never returned home.

The couple has reportedly narrated different accounts of how they had come to be caring for a newborn after LaFontaine-Greywind visited their apartment. Crews first said that she had invited LaFontaine-Greywind to his upstairs apartment and told her how to induce childbirth.

But later she said the woman returned to the apartment and handed her a baby.

A police affidavit shows Crews has admitted that "she had taken advantage of Savanna Greywind in an attempt to obtain her child and possibly keep the child as her own".

crews hoehn
Brooke Lynn Crews and William Henry Hoehn are believed to be residents of the apartment where Savanna LaFontaine-Greywind disappeared Police handout