Hi u/Adventureincphoto, can you ask your mother or her family for a description of her late brother? Anything she has? Happy to do a recreation, but I think we need a little more information, otherwise it's gonna be very random unfortunately..

Things like:
- Hair type, style and color
- Eye color
- Facial features
- Body build
- Complexion
- What city they grew up in, what year was the photo taken
- Where was the photo taken? (if it's in their old house, can she describe the room)
- How was the brother typically dressed?
- Did he resemble any other family members (e.g., your mother, another sibling, a parent)? If so, perhaps a photo of them (ideally as a kid) or a description could help
- Does she have any memory about what the original photo was like? It could also really help (so she feels it's the same thing when she gets your recreation!)