This Is Us Stars Recall the Family Members We Never Met (Beth Had a Sister?!) — Watch Video

The big happy family on This Is Us could’ve been even bigger, it turns out.

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Sterling K. Brown, Mandy Moore and Chris Sullivan, who starred together on the NBC hit, looked back at the Season 1 episode “Last Christmas” on Tuesday’s episode of their rewatch podcast That Was Us , and Brown pointed out a mysterious plot hole about his character Randall and his wife Beth: “Our kids are staying with her sister… We never meet Beth’s sister.”

That set off a cascade of memories about forgotten This Is Us siblings, with Moore chiming in: “You never meet Rebecca’s sister, either. They’re just mentioned, and then forgotten about.” Sullivan thinks his character Toby had a sister as well, but Brown corrects him: “Toby definitely has a younger brother. I remember you making mention of him.” Sullivan concedes: “Maybe that’s what it was.” (Watch a clip from the podcast above.)

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In fact, Beth had three (!) siblings we never met on the show: sisters Lisa and Renée, and brother Isaiah. (Her cousin Zoe, played by Melanie Liburd, acted as a surrogate sister of sorts to her.) Rebecca mentioned having a sister in Season 1, and we saw them as kids in a flashback, but we never met her as an adult. Toby supposedly had a unnamed brother at some point, but he never appeared on the show, either, to our knowledge.

Press PLAY above to see the cast members chat and laugh about the siblings we never met, and let us know in the comments if there are any more unexplored limbs on the This Is Us family tree.

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