Andrew Terraciano will not return as Sean Reagan in the spinoff, and Mika Amonsen will now take his place in ‘Boston Blue’

The first of what might be many shakeups has arrived for Donnie Wahlberg’s Blue Bloods spinoff.

Boston Blue will see Wahlberg reprise his role as Danny Reagan in a brand-new city as he brings his New York City experience to Boston, and one member of his family is confirmed to be joining him in the relocation. However, it’s a different face than fans are used to.

Andrew Terraciano played Danny’s younger son Sean Reagan for all 14 seasons of Blue Bloods, but he will not return in the spinoff. Instead, Mika Amonsen has been cast as Sean in what will be a series regular role, PEOPLE can confirm.

Sean’s move to Boston will play a significant role in Danny’s storyline in the spinoff.

Sean was still in high school in the Blue Bloods finale, but it seems he might be aged up a bit in the spinoff.

Amonsen’s version of the character will see Sean as a patrolman for the Boston police department, where he will be committed to following in his family’s legacy but on his own terms.