After seriously calling a popular fan theory into question last week, “How I Met Your Mother” officially put the nail in the coffin on the idea of Barney’s half-sister Carly becoming Ted’s wife.
In last week’s episode, Future Ted revealed that his children’s mother played bass at Barney and Robin’s wedding. Noting that he never would have met her had the couple taken his advice to hire a DJ rather than a band, Ted effectively revealed that she was not Barney’s half-sister.
No matter how estranged Barney and Carly, it seems implausible that the only way his half-sister would been at the wedding–let alone ever in a scenario in which she and Ted could have met–was as a member of a random wedding band.
This week, the writers went one step further by casting “Pretty Little Liars” star Ashley Benson in the Carly role. Benson guested as a hot twenty year old who fetishized Ted’s “old” age; until learning the identity of Ted’s new flame, Barney urged Ted to seal the deal so he could enjoy the vicarious experience.
Introducing Carly at this stage of the game–and giving her a persona unlike that of the titular Mother–rules her out as a candidate for that mystery character.
Though the writers never gave a clear reason why Carly Whittaker was a leading candidate to be The Mother, she represented an intriguing option and thus a popular fan choice.
Known to be studying in the city, Carly theoretically could have been in the infamous Economics class and living as Cindy’s roommate, two important clues to the Mother’s identity.
Her connection to Barney would have provided a reason for her attendance at the all-important wedding. It would also have allowed the writers to select a Mother that had some connection to the group without having to re-introduce a character who had already appeared on screen.