Janet MacKenzie is the sister Jenny is named after.

You’ll be forgiven if you only expected to see four MacKenzie siblings when Outlander: Blood of My Blood started. After all, we only really meet or hear about four of them.

There was a fifth sibling included in the TV series. This sibling was a sister named Janet, who didn’t get a lot of screentime, but when she did speak, there was a meaning behind her words, or it helped to tie up a moment.

As the series got started, there were many questions about who she was and why we didn’t hear about her in Outlander. Let’s dive into that family tree.

Janet MacKenzie is the namesake for one of Ellen’s children

We meet Janet MacKenzie in the first episode of Outlander: Blood of My Blood, and she’s also in the second episode. Once the issue with who will become laird is over, we don’t see Janet again until the end of the season, when it’s time for Ellen’s wedding. This all makes sense considering she’s already married.

Janet isn’t mentioned much in Outlander. In fact, I don’t remember her being mentioned in the TV series, and it’s the books where we get to know a little. That little fact we hear is that Jenny Fraser Murray is named after Ellen’s younger sister.

Janet did keep her name MacKenzie, and that’s because in the Outlander books, she marries another MacKenzie, although in some places, he is named Alexander Hay of Crimond. Ellen helped to arrange the marriage, and in Outlander: Blood of My Blood, she apologizes for that, but Janet is quite content in the marriage that was arranged for her.

Janet MacKenzie must die young in the Outlander world

What we don’t know is how Janet died. It’s likely that she died before Jenny was born, as that would likely be why Ellen named her daughter after Janet and not Jocasta or even after their mom, as would have been the tradition.

What we know from the official Outlander companion book, The Outlandish Companion, is that Janet and Alexander never had any children. It’s possible that she and their first child died in childbirth, but it’s also possible that she died before being able to conceive.

It’ll be interesting to see how Outlander: Blood of My Blood adapts this storyline. After all, will Ellen get to see either of her sisters again now that she has run away with Brian? In the books, we’re constantly told that Ellen cut herself off from her family, but the TV show is sure to go a slightly different route.

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Outlander: Blood of My Blood is available to stream on STARZ.