be at somebody's side
stay by somebody's side
not leave somebody's side

He has not left our son's side since the accident.

He was never, ever going to leave her side again.

I would never leave your side for a moment if it were possible.

Miles had left, his wife's side and was looking about the area.

He had heart surgery, and I never left his side.

York is also present, and has not left her side in days.

I never left her side, not for a single moment.

Would that you had married her at once, and never left my side.

But in the days since then he had hardly left her side.

They have both tried to get me to leave her side, but how could I do that?