It's pretty normal what you're experiencing.
Even in the future, you should play with each cat behind a closed door from the others to get a full play experience, otherwise one can become a "wallflower".
Our cats are pretty bonded. They play with and groom one another daily. But we still have playtime for them that is separate.
When he was eating earlier, you taught NC that you don't take another's food. It might take some more teaching but you can continue this and RC will learn to eat in peace.
Even in the future, you should play with each cat behind a closed door from the others to get a full play experience, otherwise one can become a "wallflower".
Our cats are pretty bonded. They play with and groom one another daily. But we still have playtime for them that is separate.
When he was eating earlier, you taught NC that you don't take another's food. It might take some more teaching but you can continue this and RC will learn to eat in peace.