I'd say she seemed about 55 ... I can't remember about his parents, but yeah, it's pretty weird wanting to be called "Grandad" when you're not. I wouldn't have been okay with "Dad" for a step-father either. The Doctor's usually anti-gun - Four (Tom Baker), I remember, definitely was. But I think the writers just found it convenient if SOMEONE shot the Doctor's enemies, so long as it wasn't the Doctor. It's pretty difficult to find ways out of the situations they get themselves into without violence. The "turn their weapon back on them" ploy starts to wear a bit thin, as does the "if only we all wish hard enough" ploy.