Is Walt Disney's trauma. No matter how a movie evolves, eventually the Mother always dies or is not around, which is what happened to WD. His Mother passed away when he was a kid. Sad, but true. And he imprinted that in all of his movies, the old ones.

Creates instant trauma for the character and instant sympathy from the audience

I always assumed it was so kids who had lost a parent knew they weren't alone in their loss

It’s mostly older Disney movies that were influenced by Walt! But a lot of it is derived from terrible fairytales. Like the true stories are just unfathomable. However, with that being said tangled, has both mom and dad once she finds them again.

Brave

Well, Frozen did have both parents at the beginning.

Rapunzel, mulan, sleeping beauty, moana im not sure, luca, encanto, rebel

Turning red or whatever that movie is

The incredibles.. but it has something to do with Walt Disney buying his parents a house and 1 or both of them died in the house due to carbon monoxide poisoning

Moana! :)