Prove it.

[OP: ]

Nolan knew the reason her son went up wasn't something simple even though he had tried hiding it. 

He might be the best actor of this world, she was her mother. She knew even when he was feeling something special, catching his little act was a simple thing for her.

However, even though she was a master of bluffing and economic politics herself, it was difficult to figure out her son's intentions sometimes.

He was young, but he was too good that even she sometimes faced difficulties finding out his intentions.

But, it was fine.

She was his mother. She didn't need to know everything he was doing since most of the things he did, were either for them, or for his lovely fiancée.

She understood her little son well so, today as well, she knew he didn't just leave her alone for something simple.

He might have went upstairs to greet his Lady, or perhaps they suddenly had an urge to do something hot.