Red Dead Redemption 2 contains many Easter eggs. Some of them are related to the first part of the game. For example, the saddest of them is associated with Bonnie MacFarlane, the main ally and later wife of John Marston de RDR 1. According to the scenario, their marriage soon breaks up.
In the second part of the game, Morgan finds a dying man on the shore of Iron lake. He'll be unconscious, but he'll Wake up as soon as Arthur gets close to him. He would hold a letter addressed to Bonnie to his chest.
"Dear Miss MacFarlane, I apologize. Yes, I said that. You were right, my mind no longer obeys me. And it always has been. Despite this, I love you and I know that we are meant for each other. I saw in my dreams how we raised our children and we were happy together. Dreams don't lie, and neither do I.
I'll make a fortune and be a great husband to you and a father to our children. No, I'm not bragging to you. But I have so much to say. And I will definitely write another letter, but even without it, I can firmly tell you that we will live happily ever after. Even your father will accept me, despite my simple background."
After that, the person will die. Next to it, Morgan will find a chest with money and whiskey, as well as a watch and other items inside. You can keep them.
