When will grandma leave when she dies and marries her granddaughter?

You'd better go at once. It's not the old society now. There is no such thing as marrying a woman and splashing water. If you have the heart, of course you will go as soon as you receive the news that grandma is ill. There is no need to pick anything auspicious. If you don't go early, you may not see the last time. May leave regrets.