So sorry to hear about the loss of your brother.
I too lost my younger brother to a rare disorder......it was almost 4 years ago and not a day goes by that I don't think about him.
He was in Hospice for quite a while which allowed for us to assist in his transition with dignity and grace.
I find that what helps most when I miss him are all the wonderful memories we shared together.
May those memories you had with your dear brother help you through those moments when you are missing him most.