Board Thread:The Panopticon/@comment-45314928-20200525010944/@comment-1789834-20200525195440

I think anyone who has watched the show can agree that companions have a few roles, the biggest of which is being the Doctor's aide. Asking the questions that matter and helping the Doctor to reach the conclusion of the story. Sarah Jane plays that role quite well in Journey's End, in my opinion. "But what about the Earth? It's stuck in the wrong part of space!" she asked, thus ticking the 'asking the important questions' box. Then she aids the Doctor with K9 plus Mr. Smith in returning Earth to its original co-ordinates.

If SJ hadn't have done any of that, would that detract from her role in the story? I don't think so. If the writer had incorrectly written a role with no questions and no action, she'd still be the Doctor's long-standing friend. Her being the Doctor's 'companion', or 'friend', or whatever, has been well established. Her presence aboard the TARDIS and helping to fly the Earth back home is enough to call her a companion, in my opinion.