I couldn't help grinning for a moment in the darkness.

Rose could not help grinning at her faithful companion.

He couldn't help grinning at the humor in her voice.

When she smiled at him he couldn't help grinning back.

Claire made embarrassed-suppression motions at him, but couldn't help grinning back.

He had a quick infectious laugh that you couldn't help grinning at.

Kris gave her head a little shake of denial but she couldn't help grinning slightly.

But he couldn't help grinning along with everyone else over the antics of the two creatures.

I could not help grinning at him when I opened the door and saw who it was.

I try and keep a straight face, but I can't help grinning at myself.