I'm not sure why I'm so upset by the news today about the death of Elisabeth Sladen. Perhaps it's the way in which I first found out about it, via Twitter and unconfirmed, allowing for the strange sense of optimism that maybe it's not true mixed with fatalism that it probably is (It could be a hoax! An unfortunate miscommunication! Something, anything...), or perhaps it's that her death comes as she's found a second flush of fame with the Doctor Who spin-off, The Sarah Jane Adventures. For whatever reason, it's very sad news.

Sladen was an oddity in Who circles, one of the few - the only, perhaps? - actor to have returned to the series following its revival in 2005. It wasn't the first time she's come back to the show following her original three year run between 1973 and 1976, nor was it surprising that her character, Sarah Jane Smith, was the one chosen to return in the new series; Sladen had managed to become a fan favorite during her short stay on the show - There was media outcry when it was announced she'd be leaving, and for many people (including director Edgar Wright), she was the definitive Who companion - and she had already returned to the character a couple of times since, with both the spin-off pilot K9 & Company and charity one-off Dimensions In Time.

Her non-Who work was relatively minor; she had guest roles on long-running British series like The Bill and Peak Practice as she went into a period of semi-retirement to spend time with her family. But her re-appearance in 2006's Who episode "School Reunion" proved not only poignant but successful enough to land her her own spin-off series, the kid-friendly Sarah Jane Adventures, which launched in 2007 and was due to shoot its fifth season this year.

Sladen is survived by her husband, Brian Miller, and her daughter Sadie. She will be missed.