Lawyers for Aaron Hernandez's daughter are suing the NFL and the New England Patriots over his death.

The $20 million lawsuit filed in federal court in Boston on Thursday claims that the team and league deprived Avielle Hernandez of the companionship of her father. The suit was filed by Hernandez' fiancée, Shayanna Jenkins-Hernandez, on behalf of their daughter. The lawsuit is separate from a $1 billion settlement in which the league agreed to pay families of players who suffered brain damage because of repeated head trauma while playing football.

Jenkins-Hernandez claims the NFL and Patriots were fully aware of the damage that could result from repetitive impact injuries, and failed to disclose the information, treat or protect him.

Hernandez has officially been diagnosed with the degenerative brain disease chronic traumatic encephalopathy. Boston University School of Medicine released today through its Twitter account that Hernandez was indeed suffering from CTE, and was at Stage 3 out of 4 (with Stage 4 being the most severe).

CTE can only be diagnosed in an autopsy. Hernandez killed himself in April in the jail cell where he was serving a life-without-parole sentence for the 2013 murder of Odin Lloyd, just days after he was found not guilty in a separate double homicide.

Boston University School of Medicine Twitter