Talk about the end or no

I'm visiting with my dad, he's so weak from cancer, he can barely talk every couple hours. I have not been talking about Heaven or him leaving earth in any way. I know he's sad and nervous of how aggressive this cancer is. Should I say You'll always be with us? I did last week in passing quickly, but I want to say it again. He could pass any day. Or just hold his hand and say we love you???