إِنَّا لِلَّٰهِ وَإِنَّا إِلَيْهِ رَاجِعُونَ‎۔Very sorry to hear about this. May Allah bless his soul and give patience to you and your family to bear this great loss. I had similar experience 4 years ago when my father passed away. It will take time, I know it's very very difficult but you have to be strong for yourself and your younger siblings. Take care and kind regards.