Here's one of those rare posts where I write about something completely unimportant. In this case, the silly television show "Brothers & Sisters". If you are willing to read some nitpicking, and have watched Episode 14 of the fifth and final season, or don't mind seeing spoilers about it, go on reading.
Well, it's deja vu all over again. This show might as well be renamed "Your Papa Ain't Your Papa, But Your Papa Don't Know", as the old song goes. If Brody turns out to be Sarah's father, she'd be the third character to have her paternity surprisingly switched around on her. The fourth season would be the only season where nobody changes daddies: Season One had Rebecca's father change from John Doe to William Walker, then in Season Two it changed from William to David. Season 3 had Ryan discover that the man who had raised him had been cuckolded, and that William was actually the source of his Y chromosome.
Now Brothers & Sisters Paternity Crisis #4 is not only repetitive, but also comes with a continuity error. When Sarah confronts Nora about the possibility that Brody may be her father, Nora says it is impossible, since Brody's blood type is O and Sarah's is AB. Great, paternity crisis averted. But wait! Do we have a maternity crisis on our hands?
In Season 3, Tommy's daughter was in urgent need of a liver transplant. She needed a donation from someone with her own blood type, which was O. Kevin and Justin were both Type O, and Nora said she too was an O. Now, Type AB Sarah can't be the daughter of a Type O parent - so not only is Brody out of the running, so is Nora!
No, Sarah wasn't switched at birth. The writers just forgot that Nora was an O. Had they said that Sarah was Type B, they could have had the same exact story line - since a B can have one Type O parent, but not two. Well, never mind. Just imagine that when Nora says "you're AB" she's actually saying "you're a B", and the goof is fixed.