If the doctor had noticed her reaction, it didn't show.

More than that, you will be able to watch Fanchon and notice her reaction.

Now of course she would never stop; she had noticed his reaction to it.

Aybee went on as though he had not noticed her reaction.

Her back was turned and she did not notice Cracker's reaction.

He had noticed her reaction to wrongdoing when she heard about it.

The young man noticed her reaction and pulled a face.

"Why did you let Tom come in here and watch if I wasn't supposed to notice his reaction?"

I couldn't help but notice the Government's reaction to the report.

Or maybe she was too tired to notice his reaction.