This was so hard and took like a day but I finally finished it
I’ll update with a detailed version of my headcanons later because I’m tired and not bothered to write it out right now
Some short things I will say for now though are

Twilight Velvet is the only child of Twilight (basically g1 Twi)
Night Light is the older brother of Jackpot
Mr and Mrs Shy (still thinking of real names for them) are more extroverted than they are in the show.
Hondo Flanks is a retired Hoofball player
Bow Hothoof is a retired Wonderbolt
Windy Whistles is half bat pony, and has 2 mothers.
Igneous and Cloudy are not Pinkie’s real parents.
There’s literally nothing I can expand upon when it comes to Pear Butter and Bright Mac cause they’re the most developed in the show
If you have any questions ask away
I hope u like them eeeeeeee