Yes, triangulation can happen with more than two people, and can turn into multiple layers of it.

Even if dynamics are hard to entangle, I feel that it does require one or more people to be willing to change and adapt--that's where the magic is.

Memorable moments might be someone realizing that someone has been neglected (but not intentionally) and then makes changes that somehow alleviate a lot of the tension.

Ex: Parents realize one kid has misunderstood their good intentions behind an action-- and go out of their way to spend more time with that kid. Kid becomes happy, kid stops acting up, and parents are surprised that it was all that it took.