This Is Us fans' hearts collectively shattered during the show's Thanksgiving episode, when Randall (Sterling K. Brown) finally discovered that his mother, Rebecca (Mandy Moore), had known his birth father, William (Ron Cephas Jones), for Randall's entire life. Well, keep the tissues ready, folks, because Randall's (and our) pain is only going to get worse.

Tuesday's episode will reveal how and when Rebecca sent that letter to William with the picture of Randall in it, which gave away their relationship in the first place. They did, in fact, meet again -- and their second meeting will be even more devastating than their first.

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Rebecca's motives for keeping William a secret, even when young Randall began asking about him, also become a little clearer by the end of the episode... But they aren't enough to justify what she did to her adopted son.

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