Lady Sybil

Since the beginning of Downton Abbey, Lady Sybil has been the most beloved Crawley daughter -- by the fans, by the staff, by her family -- thanks to her sweet disposition, sunny outlook and refreshing discarding of that century's conventions.

RELATED -  Another Death is Coming to Downton

And while her return to Downton was initially rocky as Lord Grantham was not inclined to accept her husband, the family's former chauffeur Tom Branson, the fact she was with child helped ease their re-entry.

So when Sybil succumbed to preeclampsia after giving birth to a baby girl, the entire household (not to mention the audience) was beside themselves with grief. Even the normally-steely Thomas couldn't help but bawl over her devastating passing.

Perhaps most heart-breaking of all was watching Branson cling to his dying wife's hand and beg her to stay, for his life -- much like the show -- is incomplete without her. Watch!

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