I grew seeds of ecsd (Chaco) x C99 from Gmanwho. These are fresh seeds from #7 male from those x Sister.
I'm not a fan of Sister, she reeks in veg, smells like lemon pledge at harvest, but after cure she only has a musty sour milk kind of smell. High is OK but nothing like D. She does cross well so I keep keep her around.
Is the sister your running the original 1991 sister and not the 2006 s1 Sister?