World Enough and Time

He's never spoken it in a TV episode.

So what happened in "Deadly Assassin"? Did someone try to force him to say it?

It wasn't even canon that he *had* a wife until the RTD era.

I thought he had a granddaughter from the beginning. Doesn't that imply a family, including a wife?

There was this elaborate theory by a previous show-runner that all Time Lords were grown in vats.

I've heard of that. I thought it was a sort of joke.

He could say it when naming a baby. He could say it when confronting some dreadful entity from Gallifrey's mythological history. I dunno...

Hee. Lots of possibilities.