I'm so sorry Revo, just reading about you getting the chance to talk to your dad alone is making me tear up, and I have never been in that situation. I guess I am picturing how that would be if I was in that situation with my mother. I am glad though that you got that alone time with your dad to talk to him, even if you're not sure what he understood. But I bet he understood more then you could know, just like Safila said. I hope it gives you peace that you had that chance to talk to him and let him know how you felt.
That is very sweet how you and your siblings are trying to make a good Mother's Day for your mom. It will be hard on of all you, but at least you have each other for support. Your mom is very lucky to have such sweet and caring children.
I wish I could say more, but I am not sure of the right words to say for this situation. I really feel for you and your family though, it's really the hardest thing to ever go through, losing a loved one. I'm sorry Revo.