Watch the "Time to Start Saying Goodbye" clip from This Is Us Season 6 Episode 17. The NBC drama series stars Milo Ventimiglia, Mandy Moore, Sterling K. Brown, Chrissy Metz, Justin Hartley, Susan Kelechi Watson, Chris Sullivan, Jon Huertas and Alexandra Breckenridge.<br /><br />This Is Us Season 6 is streaming now on Peacock!