Boston Blue is set to premiere this fall, and a major recast is offering new insight into Danny Reagan’s life since Blue Bloods. Variety reports that Danny’s youngest son, Sean Reagan, will now be played by Mika Amonsen, replacing Andrew Terraciano.
In the spinoff, Sean has moved to Boston to serve as a patrolman with the Boston PD – a move that marks his desire to step out of his family’s shadow while still honoring their legacy. His father Danny has also relocated to Boston for a fresh start, giving the two an opportunity to rebuild and strengthen their bond.
Amonsen’s casting signals a more mature and independent take on Sean, a shift that complements the show’s themes of growth and family.
Family remains the heart of Boston Blue. While the series introduces the Silver family to expand its world, the Reagans’ presence – especially Danny and Sean’s dynamic – keeps the emotional core intact. As Frank Reagan once said, “No matter the hardship or the loss, this family does not stand down. Ever.”
Boston Blue will continue that legacy, blending new beginnings with the timeless strength of family.

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