One of the rules that I imposed for kid movies in our house can be summed up pretty simply. The movie must be good.
This eliminates quite a large selection of crap. In practice, this meant that the early child movie selections in our house were heavily dominated by movies made by Pixar and Studio Ghibli.
My Neighbour Totoro is a 1988 movie written and directed by Hayao Miyazaki and is beautiful and wonderful.
I don't remember the first time the kids watched it. Well, I do remember that time, but I don't remember precisely when it was. I'm pretty sure Paige was communicating reasonably well by then, so that would put it at late 2016 at the earliest.
The central characters of the movie are two girls who move with their father to a new house to be closer to the hospital where their mother is.
The kids enjoyed the movie. They laughed at the silliness of parts. I enjoyed it, it's great. Hillary found large parts hard to watch. She related too closely to the sick mother who had to be away from her kids. It touched far too closely to some of her deepest fears.
The kids would request this movie from time to time and we mostly agreed to it. Until the summer of 2017 when Hillary was definitely ill, but had not yet been diagnosed. The kids asked to watch it one night and her response to me was, "I can't handle that movie. Get them to pick something else."
Thus, there was a soft ban on the movie in our house for the next year. After the first couple of times they requested it and we said no, they stopped.
Fast forward to this fall. A movie night was due and they asked what we should watch. I suggested Totoro. They laughed and we all enjoyed it. They've requested it again a couple of times since then.
I don't know if they are internalizing the main plot threads yet. Or if it's just a fun movie with some serious parts in it. Still, it's good and the parallels feel like they are important.