An amused grin broke out across the Doctor's face. He was certainly old enough (so he thought), but Gabriel was certainly not the sort he'd have imagined as a son. Though there was something that reminded him of his childhood friend...

Shaking that thought off, the Doctor chuckled and turned to his desk, sorting through his notes. "Well, if you're feeling better, perhaps you should be heading back to work before they come searching for you."