Character Life-Span Development

So I am working on getting my Life-Span Development course up and running for the next term and it got me thinking about the life-span development of characters in games.
I know sometimes people just want the collection of numbers so they can beat the crap outta monsters and steal their stuff.  That is fine and I like to do that too sometimes.  Other times, most times I would say, I prefer to invest in a character and know what makes them tick.

Well this course, which I took as an undergrad many years before, has had me thinking; what effects a character at different stages of development?  Obviously we have a Nature vs. Nurture thing going on here.  In a game that can be viewed almost as Stats and Concept vs. Game system.
I have explored this a bit with my Willow and Tara conversions, but to do it properly I would need something different.  I want to look how a character develops over time, using different games.  For this I need a pretty strong character concept and games that help emulate reality at particular age levels.

Given a number of factors (games I have, books I read and interest) I would want to create a character in a modern supernatural fantasy setting.  One where magic is not known, but is real.  Why not use Willow or Tara or even characters like Rachel and Ivy or the Hex Girls?  Simple, their pasts are fixed and their futures often times are being determined by other factors; either by books or games.

But how should I do this in depth detailed life-span development of a character?  Well first I should see what games I have and what ages they cover.  I'll also use the stages from the course I am writing as a guide.  Why not.  I went to grad school for years, I rarely get to use that here.

So here are the stages and the games I think will cover them well.

Life Stage	Game
Infancy	NA
Childhood	Little Fears
Pre-Teen and Teen	Witch Girls Adventures
Adulthood	Unisystem / True 20 / Cortex / Savage Worlds
Later Life	???? maybe Mage to reflect the higher power levels?
After Life*	Giest; In Nomine

*Maybe I'll use this or not.

I am sure there must be others.
Any suggestions?

If I go with the above then I am certainly going with an urban supernatural deal.  Possibly some sort of supernatural character like a witch or vampire (shocked I know).  I did have an idea for this new game featuring two twin sisters that are witches.  Maybe I can develop them here.

Here is what I have so far.

Kim and Kelley's life had always been surrounded by the strange, supernatural and sometimes horrific.  They were both born on Oct 31, Kelley a few minutes before Kim and Kim a few minutes before her mother died.  Raised by their father Kim and Kelly began encountering ghosts at age 5.  They spent their life together learning about magic and monsters.  Then one day something happened to Kelley...

I obviously don't want to develop too much here since I want the games to help in the development.  Kim and Kelley are not a veiled reference to Kim and Kelley Deal, but they were certainly an influence.  They are more an allusion/homage to Kim Harrison and Kelley Armstrong, two of my favorite authors in this genre.  I wanted to have twins since I could assume the stats are mostly the same and then do different things in the world to them.  I plan to focus on Kim in terms of stats.  I have no idea what either of these girls look like or anything.  Kinda nice to make a new start here.

Plus I would want to include some games that detail world or character development very well.  Something like Dresden Files would be good or even OVA or Cartoon Action Hour.

Something to think about.