Boston Blue family tree

Mae Silver is the district attorney of Boston and the head of the family, and CBS calls her its matriarch.^1,2 Her father is Reverend Edwin Peters, a Baptist pastor at a church in Roxbury, who gives the family what CBS calls sage fatherly advice.^2,1

Mae was married to the late Judge Ben Silver, and the Boston Blue family tree draws him with the cross of a death, because he died before the series begins.² Earlier, Mae separated from the father of her daughter Lena when Lena was a baby, and he plays no part in her life when the series opens.²

The Silver children all work for the law. Lena is a detective and the partner of Danny Reagan.^1,2 Jonah, the son of Mae and Ben, is a beat cop, new from the police academy.² Sarah is the superintendent of the Boston Police Department.^2,1

Sarah is the daughter of Ben by another woman, which makes her the stepdaughter of Mae. Looper notes that the series does not say whether her mother is alive.² Lena is the stepdaughter of Ben. On the Boston Blue family tree, the three are therefore half siblings in two directions. Jonah shares Mae with Lena and Ben with Sarah, and Lena and Sarah share no parent at all.

Spoilers from here on. In episode 17 Mae honours the wish of Reverend Peters and tells Lena that her father is Chris Williams, a former armed robber. She leaves out that he is now the police chief of a small town near Boston.⁴

Lena goes to his precinct and meets Detective Asher Reed, who is married to the other daughter of Chris. Chris has known about Lena all along, and he tells her of her half sister Christina.⁴ The chart writes Lena’s father as unknown until episode 17, and only then does the line from Chris to Lena appear, with Christina and Asher beside him.

TVLine reports that the two actors who play Chris and Christina return in one more episode each before the season ends.⁴

The Reagans come from Blue Bloods. Henry Reagan, a former police commissioner of New York, is the father of Frank. Frank and his late wife Mary Margaret, who died of cancer, are the parents of Danny, Erin and Jamie.³

Danny is the eldest son. He was married to Linda, who has died, and their sons are Jack and Sean.³ Erin is the only daughter of Frank, and Jamie, the youngest son, is married to Eddie Janko-Reagan.³

The Boston Blue family tree draws only the Reagans who matter to the new series and leaves out the wider family of Blue Bloods, whose own chart would be larger than this one.

The two families are not related by blood or marriage. Danny leaves the New York Police Department and follows his son Sean to Boston, where he takes up police work apart from his family at home.³ CBS describes Danny as a leader in the Boston Police Department who must balance mentoring and fatherhood beside Lena.¹

Sean and Jonah are officers together, and CBS calls them the youngest Reagan and Silver pair in law enforcement.¹ The chart joins Danny to Lena and Sean to Jonah with blue lines for police partners, and it marks everyone in the Boston Police Department with the letters BPD.

Erin returns as a guest in episode 17. She works with Danny on the recovery of a kidnapped girl and admits that the family is less at ease with his move than she first said.⁴