This Is Us : Miguel and Rebecca

We all know there is a likely possibility that they were messing around while Jack was alive. How crazy would it be if Toby is their love child? That would mean that Toby and Kate are half siblings! Ewww!

I don't think so. Toby is from LA.

I don't see Rebecca as the type to cheat on Jack with his best friend. I see it more like Miguel is a slimy Eddie Fisher "I'm not happy in my marriage so I'll comfort my best pal's grieving widow with my penis." type. Rebecca, like Liz Taylor, probably found solace in the memories that they shared of her husband and didn't really care about how their relationship affected those around them.