Not Just Tentacles Season 5 - Hell's Belles - Sallie May and Lin

In the last episode of Hell's Belles (for now!), Rachael discusses Sallie May and Lin, Millie's sister and mum.
Why is Sallie so popular? Why is Lin possibly Rachael's least favourite minor character? And what is her weirdest theory to date?
Contains profanity, tangents and speculation. You know, the usual.