It had been Earth's T-Mat Control Manager Gia Kelly who'd gone back and cleared out Osgood's quarters on the moonbase three days after the Martian Ice Warrior fleet had crashed into the sun and the mysterious Doctor who had helped save the Earth had mysteriously vanished. It gave her something to do while everyone attended the man's funeral. Amongst those who knew what had happened, Osgood was a hero, and news of the man's heroic actions had already begun to be spilled. Kelly wasn't refraining from attending the funeral out of disrespect for the late Head Technician, but because she wanted to avoid the crowd and the media circus that was sure to be there trying to get answers.
Since she didn't want to be dragged into the spotlight following the fiasco that had taken Osgood's life amongst others, she would pay her respects to the man in private. Until then, she would pack up what little belongings he'd brought to the moon with him and return them to the man's family.
Most of Osgood's personal effects were pretty standard for a T-Mat technician. Aside from several sets of uniforms, there was a set of personal tools, one of those Old School hobbyist's model kits that had been popular in recent years, and several personal items that looked like they might be family heirlooms.
Kelly was more careful when handling the antiques that Osgood had brought with him due to their age and apparent fragility. After reverently placing the old U.N.I.T. patch next to Osgood's spare identification badge, she carefully picked up the exceedingly long and colorful hand-knitted scarf that had been coiled around a picture of a woman in a lab coat who could've been Osgood's grandmother, gently folded it, and placed it on top of the man's least stained uniform.
It was when she'd put the scarf away that she realized that there had been a scrapbook hidden under it. Overcome by curiosity, she opened the book. On the first page, there was a picture of a middle-aged woman wearing the scarf she'd just folded and packed away standing next to a grey-haired man in a blue suit which was labeled "Me and the Doctor". On the next page, there was a picture of the same woman, this time slightly younger, who was standing next to a man in Victorian attire.
Flipping through the book, it became apparent that the photographs had been placed in reverse chronological order. The young woman turned into a girl and then vanished entirely, being replaced by a man in glasses who was wearing one of the early U.N.I.T. uniforms who steadily grew younger until he too vanished entirely following a picture labeled "Dad and the Doctor". There were still more photographs in the book however.
When she reached the photograph labeled "The Doctor, Jamie and Zoe 1969", she dropped the book.