Explaining the Recasting of Donnie Wahlberg’s Son in Boston Blue Bloods

Boston Blue has taken significant measures to win over the Blue Bloods audience, yet some viewers remain curious about the decision to recast Donnie Wahlberg‘s character’s son.

Wahlberg’s character, Danny, was introduced to Us on Blue Bloods, which debuted on CBS in 2010. The series garnered a solid fanbase, who expressed discontent when rumors circulated about the show’s potential cancellation amid cast and producers agreeing to a 25 percent pay cut.

In an exclusive chat with Us Weekly in April 2023, Wahlberg expressed his aspirations for Blue Bloods to reach a level of success akin to that of Law & Order: Special Victims Unit.

“Ice-T and Mariska Hargitay have been at it for so many years, and we hope to last as long as they have,” he remarked. “I try to stay very present with each episode, engaging with each script as it arrives, asking, ‘What’s happening now? What’s my role this week?’ This approach helps me find the journey in each episode without getting stressed about the future.”

Wahlberg also voiced openness to a Blue Bloods spinoff, joking, “Danny and Erin become private investigators and relocate to Hawaii, but that felt too similar to Tom Selleck’s iconic 1980s series Magnum, P.I., so we scrapped that idea.”

Following Blue Bloods‘ conclusion in December 2024, Wahlberg found new opportunities with CBS’ Boston Blue. The spinoff, which stars Marcus Scribner, Gloria Reuben, Ernie Hudson, and Maggie Lawson, features many familiar faces except for Danny’s son Sean, who transitioned from being portrayed by Andrew Terraciano to Mika Amonsen.

Co-showrunner Brandon Margolis supported this decision, expressing admiration for Terraciano’s growth on-screen. In an October statement to TV Insider, he mentioned, “It creatively made sense to find an actor with a different energy.”

Margolis concluded: “It was indeed a risk to introduce new faces, but the story demanded a fast connection, starting with a heroic moment that ends tragically to bring Danny Reagan into this narrative.”

Amonsen officially debuted as Sean shortly after the announcement regarding the recasting.

“Sean has moved to Boston to embark on a new journey as a Boston PD patrolman,” CBS described at the time. “He’s dedicated to pursuing his family’s heritage but on his own terms, which entails joining a department outside his hometown. Danny’s decision to remain in Boston provides this father-son duo an opportunity to reconnect on a deeper level.”

Continue reading for insights on the surprising recasting news and its implications for Blue Bloods‘ spinoff, Boston Blue:

The Key Players

Blue Bloods, which premiered in 2010, chronicled the lives of the Reagan family, many of whom serve in the NYPD under the leadership of NYC police commissioner Frank Reagan (Selleck). Frank’s father, Henry Reagan (Len Cariou), was also pivotal to the show, along with Frank’s children: daughter Erin Reagan (Bridget Moynahan) and sons Danny (Wahlberg) and Jamie Reagan (Will Estes).

Danny was previously wed to Linda Rose Reagan (Amy Carlson), with whom he had sons Jack and Sean, before her passing. Andrew Terraciano portrayed Danny’s youngest son throughout the show’s 14 seasons.

The Gist

After Blue Bloods concluded in 2024, CBS announced a spinoff titled Boston Blue. Wahlberg’s character remains central in this new series, which follows the former NYPD officer as he takes on a new role with the Boston P.D. He teams up with detective Lena (Sonequa Martin-Green), the eldest daughter of a prominent law enforcement family.

In July, Amonsen was cast as Sean, but no official reason was provided for the recasting.

What Has Been Said

“We appreciate Andrew and his contributions over the years on Blue Bloods. Ultimately, we’re exploring a new chapter in both characters’ lives,” Margolis explained to Variety in October. “This transition not only marks Sean’s entry into the family business but also places Danny Reagan in the role of a father to a cop for the first time.”

Margolis described the switch as “an organic opportunity for a fresh performance that captures the change.” The writers were eager to delve into “new storytelling avenues” with the spinoff series.

“It’s the same character and relationship, yet entirely different,” he added. “We admire what Mika brings to Sean with his vulnerability and quest for validation. Watching it come to fruition has been amazing.”

What’s Next

Amonsen’s portrayal of Sean leads the cast of Boston Blue. The new series focuses on Sean’s efforts to advance within the department alongside his friend and coworker Jonah (Marcus Scribner). Danny, who remains in Boston to support his son, continues his work with Lena at the Boston PD.

“There’s been some negativity, undoubtedly,” Amonsen noted in an exclusive interview with Us Weekly about taking over the role. “However, amidst that negativity, many fans have rallied for Sean, expressing their enjoyment of the character I’ve created.”

He emphasized his desire to make Blue Bloods fans proud with his performance, stating, “They’re genuinely appreciating the show and are excited about Sean’s direction, which brings me joy.”

Amonsen mentioned feeling “a tremendous amount of pressure” regarding the situation.

“I felt compelled to honor the previous portrayal, as I wanted to respect Andrew to the best of my ability. I made certain visual choices, such as hairstyle and demeanor, to keep Sean true to how fans have come to love him — all out of respect for the character and Andrew’s performance,” he elaborated. “The casting process moved swiftly, and I immersed myself in the role quickly. I binge-watched the later seasons to understand Sean’s evolution into adulthood and his relationship with Danny.”

Meanwhile, Terraciano addressed the changes with Us.

“I received a call on my graduation day regarding a potential new direction for Sean,” he recounted. “Shortly afterward, Donnie reached out, which was a precious moment to hear from a friend and a respected mentor.”

Terraciano expressed gratitude for his time on Blue Bloods.

“It’s been beautiful because I’ll always cherish every line and moment I had the opportunity to portray that character,” he mentioned. “Just because someone else steps in, it doesn’t mean they can’t bring something wonderful to the role.”

He added: “I had the joy of embodying Sean and now someone else gets to experience that joy. We’re both showcasing our unique interpretations while sending Sean into a new journey.”