HEADCANON TIME
sunset is a pan trans girl & the princess of compassion
twilight is bigender & bisexual
sunset is sunburst's younger sister. they were never very close & grew further apart when sunset strayed from celestia's teachings. she only found the courage to reconcile with her brother after twilight's gentle persuasion— theyre still awkward around each other, but theyre Trying their best!
sunset returned to equestria bc she missed twilight a lot. while sunset sticks with her family mostly, she and twi still visit the mirror dimension to see their human friends
twilight is the overprotective, sometimes pushy mom(though she eventually comes around & realizes its okay if her kid is kind of a fuck up) while sunset is more lax. both rlly like doting on their baby constantly
whenever their hooves are too full, they often leave night veil under Uncle Spike's care
twilight hired tempest shadow as their lead royal guard, who also acts as an mother/aunt figure to ell

it took me 20yrs to think of future!sunset's design lord help me
base- SelenaEde