The subject of the sentence is "Jamie." The phrase, "as she unwrapped the presents" is an adverbial phrase that modifies the predicate "smiled."
The subject in the sentence is "Jamie." She is the one performing the action of smiling and unwrapping the present.
Jamie smiled
She has smiled brightly all day.
She crossed her arms and smiled smugly, knowing she had won the argument.
She smiled coyly at him from across the room, hoping he would notice her.
She smiled warmly at her friend as they reunited after years apart.
Sure! "She smiled shyly when he complimented her on her artwork."
She has smiled brightly all day.
After dropping me off in the local Walmart parking lot, the little girl smiled at me.
Smile (verb) -- I smiled at the man. Smile (noun) -- She has a beautiful smile.
I smiled as I savored her scent.
She smiled warmly at her friend as they reunited after years apart.
She crossed her arms and smiled smugly, knowing she had won the argument.
She smiled coyly at him from across the room, hoping he would notice her.
Sure! "She smiled shyly when he complimented her on her artwork."
She smiled at me approvingly
The sun smiled down warmly on the field, brightening the flowers with its cheerful rays.
Sweetly is an AdverbThe birds sang sweetly.He smiled sweetly at her.
Is this sentence a appositive "grandfather smiled drew a breath and began the story always one of our favorites"