There really aren't words that take away the pain, but it does help to know there are people around you who care. I've lost both my parents and a year and a half ago a much loved younger sister. Allow yourself to grieve. Time soothes the pain, good memories will help, but there will always be times when tears will come, and that's okay too. They remind you of how much you loved the one you lost and how they will always be part of who you are.