i was once that older girl who had a younger girl call me so I know what that other older girl might be thinking. I also gave her my number but prayed silently that she wouldnt use it. She did! and HOW! she calls me all the time and its a little annoying but I will tell you that the reason why its annoying is because she tells me all day how she thinks my advice is teh most amazing thing in the world and I sometimes feel like shes squashing me!
It doesn’t have to be an older/younger relationship for that to happen. (See the relationship advice thread)
OP: I guess you’re the girl, not the counselor? As other people mentioned, I think its fine as long as no one goes overboard. It doesn’t always have to be heavy stuff, you can also call to keep in touch, before Rosh Hashana etc.
Good luck!