Our thoughts and prayers here in Central Texas are with you and your family.
When my dad suddenly passed away from an aortic abdominal aneurism, while we are a large family strong in our faith, - for the longest time it was very difficult for us as no one really knew how to act. Dad' eccentric personality was so strong (He really did make his living during the Depression as a cedar post chopper...), his absence was an engulfing silence.
Just be there for one another , as we are for you.
Pick up his mantle and wear it! It's what a family does.