Boston Blue tackled the growing tension between Donnie Wahlberg’s Danny Reagan and his onscreen son as the two struggled to coexist under the same roof.
In the Friday, November 14, episode of the Blue Bloods spinoff, Danny opened up to Lena 
about the difficulties he’d been having with Sean.
“The sandwich was for Sean. We were supposed to have breakfast, and he stood me up to go for a run,” Danny said. “I am all for the kid staying in shape, but I’m trying to spend time with him.”
Lena gently noted that living together can create its own set of complications. Danny insisted otherwise, saying, “It is going great, and we are having a great time. So I figured, why not stay longer so we can stay close?”
Later, Sean confided in his partner Jonah, admitting that sharing an apartment with his father wasn’t as easy as he hoped particularly after they argued over Danny making his adult son’s bed.
“I can’t ask him to move out,” Sean said. “He uprooted his whole life for me, and it is nice spending time with him. But I just wish he would leave at the end of the night.”
Eventually, Sean decided to address the tension directly. When he apologized to Danny for how strained things had become, Danny took responsibility as well.
“I am the one who should be sorry. I am crowding you,” Danny responded. “I think it is time I got my own place.”
The two reached a compromise: Sean moved in with Jonah while Danny stayed in his apartment, giving both Reagans the space they needed. Their evolving father-son dynamic has been a recurring theme since Danny relocated from New York to Boston.
Danny’s original journey played out on CBS’ Blue Bloods, which aired from 2010 through 2024. Boston Blue, which premiered in October, began with Danny rushing to Boston after Sean fell into a coma. Fans immediately noticed a major change Sean now appears in a new form after previously being portrayed by Andrew Terraciano.
Coshowrunner Brandon Margolis explained the recast to Variety, saying, “We love Andrew and the work he did over the years on Blue Bloods. Really, it came down to we’re telling a new chapter in both of their lives.”
Margolis elaborated: “It’s not just Sean who has joined the family business and is turning over a new leaf. Danny Reagan is now the father of a cop something he’s never been before.”
Calling the change “an organic opportunity,” Margolis said the new casting allowed the show to bring in “a new performance with a new energy” to reflect this evolution. The writers were eager to explore “new storytelling lanes” in the spinoff.
“It is the same character, it’s the same relationship, but it’s also completely different,” he added. “We love what Mika has brought to Sean this vulnerability, yet this desire to prove himself. It’s just been great to watch it come to life.”