Re didn't feel it was appropriate to argue Nyx's view of his granddaughter. She wasn't only the night, any more than he was only the sun. But it was a minor detail, so he chose to let it go. What grandparent doesn't think far more of his progeny than a stranger would?
She was right anyway for the most part. There were likely many commonalities. "I should think you are right. It stands to reason that the same things are needed everywhere, regardless of which group of gods lays claim to the area."
Re already knew there was a sun in Nyx's world. One that had nothing to do with him. What world could possibly exist without the light? He was a bit puzzled that Day and Night were both needed with a Sun, but far be it for him to judge.
It was apparent he was simply better at what he did and didn't need all that extra help. Except at night. But that was something else entirely.
"I would think the mortals would have a very hard time of things if not for our combined influences." Once spoken, Re realized it was a thought he had never had before. His family held Kemet, Nyx's held Greece-at a simplified level. The world was large, and surely there were others out there, all doing the same thing. Ensuring life throughout the world. Was there another Geb?
The thoughts actually began to hurt his brain, and he let them go. These were things meant for those of a more philosophical mind than his own. He wondered if his son would even be able to put it in terms that made sense.
"You have given me much to think about. Perhaps, as people grow in number and the world becomes a little smaller, we will find there are many, many out there like ourselves."