As Salaam Alaykum
I have a wife, 3 daughters, 2 brothers and 1 sister (parents & grandparents are all deceased). My understanding of the Quranic heirs are:
One eighth to my wife
Two ninths to each of my daughters
One ruling on the non-Quranic heirs is that my brothers get one twelfth each and my sister gets on twenty fourth.
My question is to confirm the above and if more importantly, if the ruling on the non Quranic shares are correct, where does this come from and if the understanding is that my brothers and sisters are intended to care for my family after my death, if they are not capable of doing this, and that my wife would then have to seek employment, what is the ruling.