i'm thinking on working on a fanfiction. it's focused on the harry potter world, and even though i want to make the characters seem noticeable different and grown as people, i still want to have it make sense and stay true to the story, since it happens right after the books end. any advice? thank you, love!

Thanks for your question, darling!  This is a really interesting topic to discuss, since so many fanfic writers try their hand at the aged-up AU without really thinking about what that entails.  No one really talks about it, so of course, we all go at it blindly.  But I have a few thoughts that might help :)

Writing Aged-Up Characters

I’d like to note first that this post applies best to characters aged up from 1-15 years older than their current age.  Once you start aging characters from 20 to 50 years old, the process becomes much more complicated – especially considering the life experiences in that time frame, like marriage/divorce, children, career changes, retirement, health changes, etc.  This is also a process that mainly involves list-making, so if you like lists, then you’re gonna love this (+ any of my ideas tbh I’m such a list whore).  Anyway…

Step 1: List the Character’s Traits

You were warned.  The first step to aging a character properly is to take inventory of who they are now – their negative and positive traits alike.  How extensive you choose to be is really up to you.  You can list all their major traits, their preferences and fears, down to their quirks and sense of humor.  Or you can just stick to their major traits (which is what I’ll be doing for the example list).  From experience, though, I recommend you be as in-depth as possible.

To give an example, I’ll create the character Kara Roberts:

Step 2: Separate “Developed” and “Undeveloped” Traits

So now that you’ve got your list, the next steps are to help you decide which traits to keep, which to change, and which to remove completely.  The first step to organizing your traits is deciding which are developed, and which are not.  Which traits have potential to naturally improve/escalate, while others are at their complete state?  In Kara’s example:

The process may not have been clear, so let me explain.  Traits like patience, loving dogs, intelligence, and morals don’t have anywhere to go from their current point – all you can become is more patient, more intelligent, or more entrenched in your beliefs.  Unless an external incident takes place, they don’t naturally change.

But a crush on a professor can escalate without external change – it can become an obsession, or an obstacle to education.  Or it could just fade with time.  A bad relationship with family can become worse with time apart, or better as time heals wounds.  Unless something situationally changes, these are the only two traits that are mutable with time.

So once you’ve identified undeveloped traits, decide how time develops them.  Leave the developed traits alone for now (we’ll deal with them later) and just consider how their current situations resolve over however many years your character ages.  Put that aside for later.

Step 3: Separate “Innate” and “Acquired” Traits

So we have a new list, minus the two underdeveloped traits, but it’s not our final list.  Next, we separate the character’s traits into those which are innate – those which our characters are born with – and those which are acquired.  In our example:

This is simple enough to distinguish.  Kara wasn’t born with a strong body – she was born a tiny, squishy baby.  She wasn’t born loving animals, but she learned to love them due to her experiences.  She also wasn’t born with the ideology of treating others how she’d like to be treated, because babies don’t do that.  These are all consequences of how she was raised.

So what do we do with this second list?  Reduce some of the acquired traits according to the character’s experiences.  Kara can keep on loving animals; in fact, she could work at an animal shelter and wind up loving them more.  But if she’s sitting all day in an animal shelter, her strong physique may start to go with time – or if she gets pregnant, or if she starts stress-eating – or even if she becomes an Olympic athlete, her physique would change.  And her “do unto others” belief can easily fade if life starts to hit her hard.  In fact, it’s more likely that her innocence/idealism would take a hit, as she leaves college and enters the competitive job-hunting world.

Step 4: Separate “Rational” and “Irrational” Traits

Now we’ve got an even narrower list, but we’re still not done.  Now you’re going to take the list of developed, innate traits and split it one more time: into rational and irrational traits.  Rational traits include matters of the mind, while irrational traits are based on decisions, feelings, or matters of the heart.  This finalizes the list:

Kara daydreams because that’s how her brain wanders.  She’s intelligent because it’s something she was born to have.  But patience is a matter of the heart – you’re born with a certain amount of patience, but you choose to continue being patient.  You can be born a loving child, but you choose to act in that love.  Patience and love are matters of the heart – they’re not just how the brain works.

So you have a third list, and these are the traits you don’t have to just develop or reduce.  Irrational traits are subject to change.  Kara may have been patient and loving in college, but in fifteen years, she doesn’t have to be that way anymore.  Life can change her – normal experiences can change her.  Some of these changes don’t even require an explanation, because life… just does that sometimes.

Step 5: Finalize Your Character’s New Traits

So you have three kinds of traits which you can develop, reduce, or change – but you shouldn’t do this to too many traits, or the character can become unrecognizable.  If we took all our options and made Kara a selfish, unhealthy, impatient person who’s in great standing with her family and stalks her English professor… she just wouldn’t be Kara anymore.  But instead:

So Kara’s still got her charm; she’s strong, smart, and loving… and she’s gotten over her English professor.  But her relationship with her family is still bad, and as time progresses, this wears on her patience.  As her patience diminishes, she stops waiting for things to work out in her favor – so she starts to cut in front of people, abandoning the “do unto others” ideology.

She would probably behave the same with friends, although she’d be less patient during arguments – and she wouldn’t put their needs above her own.  In a business environment, she’d probably be more successful on the career ladder – but in customer service, her impatience would prove a fatal flaw.

So she’s changed, but not completely.  We can see linearly how she’s changed and why, so we believe what we see.  And that’s what makes the whole list process worth it!  You can see exactly what to change and why, without messing with anything else.

Anyway, that’s my method of aging characters.  I hope this helps you to age up the Harry Potter characters – I personally love seeing different takes on mature HP characters, so I’ll be looking out for your fic if you ever choose to publish it!

If you have any more questions, my inbox is always open :)  Good luck!

If you need advice on general writing or fanfiction, you should maybe ask me!