Hi, aussie. I'm completely unfamiliar with this film/video, but happened to take a look at your thread, did a little sleuthing just now, and find that other sites (namely IMDb and Wikipedia) present the title as being with the "II" included, like you suggest.

Having said that, TMDb always prefers that primary presented (a.k.a. "Original") title be whatever appears on screen during a film's or whatever's opening credits; that's normally considered the prevailing title choice to go with, in instances where something might also be known by any other title.

I see that actually the bases have been covered on TMDb, in this film's case, as a contributor added the "2" and "II" variant titles to the Alternative Title field: https://www.themoviedb.org/movie/15997-the-land-before-time-ii-the-great-valley-adventure/edit?active_nav_item=alternative_titles&language=en-US Therefore anyone who may search for the title by either form, it'll come up.

I don't otherwise know anything about this film or its title and hope that the above may in some way prove helpful.

I have taken a screenshot of the opening credits title block here https://imgur.com/a/2FYfCRU

It shows the II is in there

That definitely by all means looks legit.

If with your originating post of this thread you click on the little Edit wheel, then, near the top of your originating post that'll open, switch Discussion Type of this thread from "General" to "Content Issues", then click on Submit, that'll automatically move this thread over to the Content Issues https://www.themoviedb.org/talk/category/504794a319c29527aa000640 queue of TMDb's Support forum and a moderator will see it. Only moderators are able to unlock and then revise locked titles.

Precision: It should ideally be the opening title from the original release. Not sure if that's the case here.

@WardenclyffeTower Do you remember what made you change the original title?