There’s a quote from Harry Potter and the Sorcerer’s/Philosopher’s Stone that I adore:
There are some things you can’t share without ending up liking each other, and knocking out a twelve-foot mountain troll is one of them.
I think it states in simple (silly) terms a complicated truth about friendship and relationships and the moments that cement them.
Real, lasting bonds are formed by acts of support in moments of vulnerability.
The more two characters expose vulnerabilities to each other and the more they support each other in those moments, the stronger their relationship will be.
During the troll fighting incident in Harry Potter, Harry, Ron, and Hermione’s lives are all in danger (vulnerability) and they each play a role in getting one another out of danger (support.)
This example works particularly well because there’s an equilibrium of support and vulnerability. There may be a bond between two people when one person is doing all of the supporting, but it won’t be a healthy one.
Of course, moments of vulnerability don’t have to be life threatening. They can be moments of emotional vulnerability. For example, if person A performs in a dance recital for the first time ever (vulnerability) and person B comes to watch them (support).
As humans,we don’t like to expose our vulnerabilities to people with whom we don’t already have a strong bond. When starting out a relationship, these moments are usually out of the person’s control.
For example, person A walks into a crowded classroom for the first time, looking for an empty seat and person B takes pity and moves their backpack from the seat next to them onto the floor, freeing a place for person A.
After class, person B spills the entire contents of their backpack onto the floor and person A helps pick everything up.
These two moments won’t make person A and person B instantly friends. Bigger moments strength bonds quicker than smaller ones, but the more we support people and the more we expose ourselves to them, the greater our bonds grow. The stronger the bonds, the more likely we are to willingly expose our vulnerabilities to people and purposefully deepen the relationship.
If you’re writing a relationship and you want it to be something built on solid foundations that your readers can support, you’ll want to show these moments of vulnerability and support.
Start small, with moments of vulnerability that are accidental or forced. As the bonds grow stronger, let the characters purposefully initiate the moments, signaling trust and comfort in the relationship. Level One is moving a backpack and freeing up a seat. Level Ten might be fighting a mountain troll together. Level Twenty is handing someone a ticket to your first ever dance recital.
How to Manipulate This Rule to Create Complex Relationships
Just because the foundation for a relationship is there doesn’t mean the characters have to act like it is.
A perfect relationship is boring to read about. Support doesn’t have to be given or received kindly. Especially in those first stages of the relationship. Person B can be grumpy and resentful of having to give up their extra seat to person A, and they might not want to accept person A’s help when person A helps them pick up the contents of their spilled backpack. Even once a person admits to themselves that they like the other person, two people who openly care about each other can still bicker and squabble and disagree. Supporting each other when it counts in no way precludes that.
If you want to complicate the relationship even more,if you want to write about a complex, difficult relationship: have characters fail to support each other in moments. Explore the consequences of those decisions.
As for characters who would die for one another…
Your characters should all have driving motivations. The best way to build strong relationships in your writing is to show your characters supporting each other in those specific efforts.
Show moments of support that come at a cost to the person offering it. Person B goes to Person A’s dance recital, but skips out on a date to do so.
A recommendation: show the non-POV character support the POV character in a moment of vulnerability first. We’re already in the POV’s head and we’re already on their team. We still need to be convinced by the non-POV, as the author, you have to make the reader like the non-POV character before we like the relationship. A quick and easy way to do this is to have them support the character we already like.
If the relationship is more contentious at first or your story doesn’t allow for that, a second option is to have the non-POV character do/say something that the POV disagrees with, but the reader knows is right. it will not only be a point in favor of the non-POV character, but it will show the reader that a relationship with the non-POV will be good for the POV.