The cat is coming out of the bag on This Is Us for Rebecca (Mandy Moore) and William (Ron Cephas Jones).

Beth (Susan Kelechi Watson) was finally brought into the fold when William let it slip that he's known Rebecca for Randall's (Sterling K. Brown) entire life. Now Beth must decide if she should tell her husband a secret that would turn his entire world upside down. It would not only wreck the relationship he's built with his biological father, but it would also destroy the bond he has with Rebecca, which we learned would be more devastating for him than either of his siblings.

Sterling K. Brown, <em>This Is Us</em>Sterling K. Brown, This Is Us

Randall spent most of the episode attempting to bond with Kevin (Justin Hartley), and when the two were finally able to break down their walls and have a heart-to-heart, the audience found out that Kevin has always been jealous of how much Rebecca favored Randall. To his credit, Randall admitted their mother did give him special treatment, took his side in arguments and did everything she could to make sure Randall felt included. Randall ate up all of the attention because he could never seem to get it from Kevin, who he looked up to and wanted his brother to accept him more than anything.

Previous episodes also revealed that Kate (Chrissy Metz) and Rebecca barely speak. That means that Rebecca and Randall have the closest relationship out of all the three kids -- and him finding out that she kept William from him for 36 years will undoubtedly shake that relationship to its core. For so many years, Rebecca has been the one looking out for and fighting for Randall. Finding out that she blatantly lied to him when he asked where his birth parents were is going to completely reshape the way Randall sees his mother and the way they interact going forward.

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The truth bomb will officially drop in next Tuesday's episode when the Pearsons gather for Thanksgiving dinner. Randall's initial reaction is one of shock and tears according to the official NBC preview, but this is a secret that will reverberate through this family for a long time. Randall will have to decide how he feels about Beth finding out before him as well. Kate and Kevin will certainly have their own feelings about their mother keeping such a big secret. It's bittersweet that we won't be able to see what Jack's (Milo Ventimiglia) reaction would have been, too.

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So far the series has focused on the Pearson family's perseverance and their ability to band together in times of trouble. Every obstacle has been met with strength and inevitably they find a way to overcome it. Slowly but surely, the cracks in this seemingly perfect family's veneer have started to appear; William and Rebecca's secret in the present and the destabilization of Jack and Rebecca's marriage in the past timeline. Will next week's episode begin to show the family falling apart? Time will tell, but either way you should definitely have the tissues ready.

This Is Us airs Tuesdays at 9/8c on NBC.