Karen Blackstone is the late wife of Frank Blackstone and the mother to their triplet daughters.
Frank met Karen shortly after he faked his death and disbanded his former alias "G-Man". The pair got married and together had triplet daughters: Lily, Sara and Beth.
Karen and the girls were killed when mob boss Tony Angelo ordered Frank's home to be torched due to him not repaying the crime boss back. Karen and the girls were trapped and subsequently died, much to the devastation and anger of Frank.
By the time Frank found out the truth Tony was long since dead. Frank instead settled for the two arsonists to be killed, and his wish came true when he tracked down the two men responsible, then tortured and murdered them.