Ive have her number from the start, I assume it's of you need to cancel etc, but I've only ever really emailed!
I feel pretty abnormal though in the sense, I don't look her up etc because I don't really want to know anything. I like the person I see once a week in the room, and I think if I knew more etc it might taint that in a weird way. Although I can totally see why others ant to know more etc, I think it's more common than someone like me who prefers not to know.
I don't see much harm in it and think it's natural but I suppose it's just knowing a boundary.
If I did search and found something I think I would be inclined to tell her, because I'd feel guilty in a way.
Like I say I do understand it though, and I'm sure most Ts do and probably expect it!