It is about trip's death in the last seasons end, it looks to me as if the actor was going to quit the series and he would be written out and they desided to kill him of in a fashionable way.
But then the whole series got shut down so the episode was not to be aired, and then they desided to send it anyway and it came out in a extra episode as the crew from the next generation looked back at the event that lead to his death.

I didn't like this ending as they have killed his sister in the weaponsfire against earth, and then later they kill his daughter and not enough they have killed his other world counterparts children and then him self...  they have wiped out his entire family tree, and I cant understand why this was neccesary.

Any inside infromation on this?

Don't misunderstand me, I have nothing against death of actors in leading roles, this makes it more realistic and can make a point worth noticing but this went to far by me, as I said his bloodline is gone forever