He looked again at the work going on above him and his eyes widened slightly.

His eyes widened slightly as he took in her words.

Her eyes widened slightly, telling him everything he needed to know.

It meant more to him than to her and his eyes widened slightly.

He saw her eyes widen slightly in response and she seemed to forget the question she'd been about to ask.

His eyes widened slightly as he took in those companions.

His eyes widened slightly and he turned back away from her, casually.

Her eyes widened slightly as she took his double meaning.

He thought the pupils in his mother's eyes widened just slightly.

Otherwise, but for her slightly widened eyes, there was no sign of what she might be thinking.