7; Her brothers cannot seem to put face on. "Zeus" has a reputation for not being able to keep it in his pants, Daniel is just strange and his wife stays away months at a time, and "Poseidon" has his share.

Ephraim Selwyn, father, d.
Rhea Selwyn nee, mother, d.
- "Zeus" Selwyn, brother
  - Ambrosia Selwyn, sister-in-law
    - Cadawlader Selwyn, nephew
    - Hortense Selwyn, niece
    - "Hephaestus" Selwyn, nephew
  - Various random women
    - "Athena", niece, marketed as sister
    - Liliana Selwyn, niece, one of the few bastard children "Zeus" had that actually got acknowledged as such
    - Adrienne Selwyn, niece, marketed as an orphaned cousin, twin to Aristide
    - Aristide Selwyn, nephew, marketed as an orphaned cousin, twin to Adrienne
    - Winslow Ramsay, nephew, unacknowledged, lives with family friends, does not know his parentage
    - James Fletcher, nephew, believes that "Zeus" is his godfather. Raised out of the country.
- Emrys Selwyn, brother
- Daniel Selwyn, brother
  - Freya Selwyn, sister-in-law
  - Deanna Benwick, mother-in-law

Childhood
Born a cold winter's night in '61, Tanwen is to be the first daughter and last true child of Ephraim and Rhea Selwyn. She turns out to be a quiet and submissive child, easily pushed around by her elder brothers whenever they are home from school. She grows up mostly knowing her brothers at a distance as, by the time she is four, all three are all at Hogwarts. Still, that does not save her from being subjected to their torments when they are home.

She shows her first sign of magic when her "half-sister" is born. Still too young to figure out that Zenobia isn't actually her father's child but rather her eldest brother's, she is easily confused by the anger that lurks in the house. The night Zenobia is brought home, Tanwen has enough of the fighting and accidentally spells her room into the silence that lasts the week. No one seems to be able to undo and eventually they just let the magic fade.

Hogwarts
Her time at Hogwarts was approached under a sense of unease. While she is excited, a larger part of her would be okay just receiving her magical education at home from a governess. At this point, she is terrified of new places and is expecting to be utterly overwhelmed. And she is. She retains little memory of the train or boat rides or the welcoming feast. Frankly, all she remembers is waking up in a new place donned in yellow.

She does settle in eventually and becomes grateful for her parents for refusing to allow her to stay home. She isn't sure if the whole scenario is made better or worse by the fact all of her brothers had graduated by the time she attended. She thinks they would have made it worse.

In fact, once she settles in, it seems the distance from home and family is much what she needed to grow a sense of self-confidence and over the seven years turns from someone meek to someone who does what needs to get done and doesn't mind getting dirty. Her friends help with this process a lot, pushing her to do things out of her comfort zone until she no longer needs prompting to raise her hand in class or stand up for herself. This shift in her views of herself prompts growth in her relationships with her brothers - "Zeus" especially. With Zeus over ten years her elder and Daniel being six, it might also help that she is starting to reach an age where they no longer consider her a kid.

It is during her first year, 1872, that "Zeus" has his first public episode of scandal and rather than marrying the girl he knocked up, he just takes the child in. Tanwen ie pissed about this whole thing and there starts her collection of unsent angry letters to her brother. When he knocks up yet another girl in her third year her parents have had enough and a rushed marriage takes place. The twins are portrayed as orphaned cousins from another country. They are getting ready good at covering up "Zeus's" 'adventures'. She can now socially acceptably refer to herself as an aunt.

She isn't too sure about her new sister-in-law, Ambrosia. The two are only a few years appart in age but Ambrosia has a far more dominate personality than her own and seems to not care for Tanwen at all.

Her performance in her classes are mediocre and she only really seems to enjoy charms and divination and when her N.E.W.T. years come around she ends up taking only four classes, charms, divination, transfiguration, and history of magic.

Methodical. Strict. Caring. No Nonsense. Stubborn. High Energy.

"Try me," is likely her motto. She's spent so many years cleaning up after her brothers that she's developed a backbone of steel and a reputation as the one you want to go if you messed up. She has a knack for getting things in order and back where it should be - objects or humans. This is why she tends to be used to care for the hoard of her brother's children. In her opinion neither he nor Ambrosia have a maternal bone in their body and that those children would be better off alone than strictly under the care of their parents or parent. They are children, not a military.

Despite her no-nonsense mentality, she is typically warm and caring to her friends and family. Soft-spoken until angered, ever since her mother's passing, she has taken to tending to the family much like a shepherd and his sheep. She genuinely loves them all. She has truly never met a stranger and would rather invite someone into her own home and care for them than leave them to fend for themselves and she often expects the same in turn. While strict under a mistake, she easily forgives and has only ever held one true grudge - "Zeus's" infidelity.  To her family is sacred and needs to be cared for and tended to. She still loves him, but they have issues.