Big changes are coming to the Big Three.

The final trilogy ofThis is Us—which will follow a different sibling in each episode—begins March 15 on NBC. Starting with Kevin (Justin HartleyKate followed closely by KateChrissy MetzRandall’s final words were:Sterling K. Brown), the episodes will highlight the decisions each sibling makes after Rebecca Pearson—who is battling early onset Alzheimer’s—tells her children to take risks and that this disease shouldn’t hold them back.

Justin teased some big changes for Big Three ahead of the emotional rollercoaster ride.

The actor said that each character was making a decision which would change their lives. Entertainment WeeklyInterview. “You will see the effect that that made on the children, and their choices as a result of that powerful speech.

“[They’re] very clear about what she wanted—until they go to do it,” he continued. He continued, “And that’s what happens in this episode: Kevin gets this idea about his mom’s wants and is on a mission like, “Okay, this will be my thing.”