Engagement Alert. One of the Stars of the NBC hit demonstrate "This Is Us" is locked in and clearly this onscreen family is acting like a genuine family in the method for not having the capacity to hold the engagement under wraps. Mandy Moore, who plays Rebecca on the show is purportedly connected with to her sweetheart of two years, independent musical gang Dawes frontman Taylor Goldsmith. So who spilled the beans? That would be her costar Chris Sullivan who plays Toby partner of Kate.