Description
In most modern text editors, when you use arrow keys to move, say, from the end of a longer line down to a shorter line, and then back up to the longer line, the cursor goes back to where you were when you first moved down; it doesn't move you directly above the end of the shorter line.
This is a more ergonomic experience that I think most people are used to, and the same applies to the tree: if you move from a child to the parent, when you move back down again, you should return to the same child you came from, not the leftmost child. This should apply to entire chains, so that I can traverse the tree from bottom to top and back to the bottom, returning to the leaf I originally started from, all by pressing up up up up up down down down down.
This should also apply in the opposite direction once multiple parents are implemented.