Hi Allie and O&CYou two seem to have things in hand in drafting 'the letter' to your sisters. I agree two pages is too long and remember all the plans you made for your son, unravelled at the last moment, with a simple "I'm trans'. (that was so funny).
You and O&C are getting too esoteric. Keep It Simple Stupid (KISS) principle is what you should probably use. So might I suggest the following structure / outline?
Dear sister
I have to tell you something and its a very private matter about me. I'm well and healthy, so please do not worry about me in that regards. My wife has also known about this, for a long time as well and she also helps me in this private matter. I would very much like to tell you in person (with wife). But distance is a problem, which precludes us from doing so.
I'm transgender meaning I have always been a female and I have been transitioning for the last period of time.
Some pertinent facts:
1. Electrolysis
2. Hormones.
3. You can still call me 'your brother' (just like you did with your son)
I have sent a similar letter to your sister telling her about me.
I have already told our son and he is fully aware of what I'm doing and he fully accepts and loves me unconditionally.
I would love / like to talk with you, about this private matter and answer any questions you may have in regards to this matter, if you so wish to do so.
I will always love you no matter what happens between us.
Your loving sister / brother
Allie / (deadname)
I also agree that you absolutely must, without a shadow of a doubt
let your wife proofread this letterI hope this provides food for your thoughts. I would like you to think about what your sisters thoughts could be about this matter. Maybe bounce this question of your son? Then you can decide what to do from there.
Your sister from across the pond and I hope you come up with a wonderful letter to your sisters.
Love and Hugs to both of you, alwaysSarah BPS Full Disclosure, 'I'm no expert on this'
@Oldandcreaky @imallie