I am looking for a story where souta comes thru the well and someone had killed their mother and grandfather. It's a three part story I believe and sesshoumaru was cursed to be a human for some of it and he has a kid.

Hola! La primera parte de tu relato se parece a "A Miko's Peace" de M-Angel 05, Rated MA, aún sin terminar.

www.dokuga.com/fanfiction/story/9957/8

Espero haya ayudado!

I think what you're looking for is Alpha Pack Mates series from Hairann

I am Alpha!
It matters not if you are youkai or ningen, if you're male or female, young or old, weak or strong, no it matters not in the end. All that matters is who is Alpha and who isn't. Brothers fighting for dominance, mikos fighting for control, who will end on top, who will have to submit? What's an Inu pack to do when there are far too many Alphas? Book 1 of Alpha Pack Mates series.
Rating: MA

They are Pack
Book 2 in the Alpha Pack Mates series. A new pack member, blossoming romances, a wedding, completion of a quest, and learning how not only to be a pack, but also to be a family. Find out what else is awaiting the inu-tachi and get answers to some questions from Alpha.
Rating: M

We are Mates
Just when Kagome thought the worst was behind them, she discovers their fate has only begun. Now more than ever before, Kagome must lead her pack into the next stage. Welcome to the third and final book of Alpha Pack Mates. Won joint third place best Kagome portrayal, Dokuga awards 2nd Q 2010! Now complete! Nominated best action/adventure and best portrayal - Kagome Dokuga awards 2nd Q 2011.
Rating: M