BOSTON » Part of the three-month mystery of "Baby Doe" has been solved but authorities are expected to fill in details when two people charged in the 2-year-old girl’s death appear in court.

Millions viewed a composite image of a brown-eyed, chubby-cheeked girl, dubbed Baby Doe when her body was found June 25 in a trash bag washed up on a Boston-area beach.

On Friday, authorities released her name — Bella Bond — and announced charges against her mother and the mother’s boyfriend, saying they finally had a tip that broke open the case.

Michael McCarthy, 35, is charged with murder. Bella’s mother, Rachelle Bond, 40, is charged as an accessory after the fact. They are to be arraigned Monday in Dorchester District Court in Boston.

Investigators have not publicly speculated on a motive or a cause of death in Bella’s case, saying more will be disclosed at the arraignments.

McCarthy’s attorney, Jonathan Shapiro, declined to comment Sunday on the case except to say that he expects McCarthy, who has been hospitalized, to be in court Monday. Repeated attempts to reach relatives of McCarthy have been unsuccessful.

Bond’s attorney, Janice Bassil, did not return a message Sunday seeking comment.

Bella’s biological father, Joseph Amoroso, said in media interviews that Rachelle Bond told him McCarthy killed their child. He also told The Boston Globe and the Boston Herald that Bond told him McCarthy believed the child was possessed by demons, and that Bella had been dead several weeks before her body was found.

Amoroso said he has been in Florida for a couple of years and returned to Massachusetts in August hoping to reconnect with his daughter, whom he never met. He said Bond told him last week what happened to their child, and stayed with him in Lynn on Thursday night. He said he was questioned Friday. Amoroso has not been charged.