where did katya go? (possible spoilers)

I wondered about that too. i think maybe by then she was a teenager and there wasnt really any need for her to happen to be with yuri jr and lara all the time but i would have thought she'd have gone to yury's funeral!! confusing

It bothered me as well; I haven't gone back to check the novel, so I'm just offering a thought... Komarovsky was involved with Lara's mother until Lara came of age...is it possible that she was able to get away because she left Katya with him, to be the next in line?

In the Book and 1965 Movie when Lara leaves with Komarovsky for
Vladivostok Katya is never mentioned again. It is possible she
is with Lara as she seeks to find her younger half-sister in
Moscow. Also in this version they contradict the book and the
Book and 1965 movie by showing Lara's child w/Zhivago as a
boy when the child was a girl.

I imagine they didn't show her at the end of the film because she would have been the same age as Keira and that would have looked wrong. I assumed she could tell her son to run away because he could go to his half sister who would look after him.

Protector of Percy. He is grand and not at all bad. Honest

I guess most viewers showed good will for the characters in the film. But it was a tragic time. As Yevgraph said in the beginning many children had to eat human flesh to survive in the period. Katya was the daughter of Lara whose was the wife of Pasha who died in the power-struggle after Lenin took control of the whole Russia. So Katya could just be killed when Lenin wanted to cleansing all the families of his opponents in the communist party. So Katya could just died of disease, be shot, flee to China (with Komarovsky), ....
But I think since Lara did not mention Katya again and focused on her second daughter, I would not be suprised that Katya was already dead.
It was a tragedy of millions of people.