Challenge of challenge #14

Reconnect with someone from our childhood.

So this sounds like it would be easy, maybe. However, I'm struggling to even start. I have two people as options in my mind, one from nursery school, however I have not spoken to her since I moved from my first to second school, when I was 5. 15 years ago. Long.
The other option is a girl who I've known since before birth...Yep.
Our parents shared ante-natal classes. I think it'd be fun to get back in touch, but yet again its tricky because I live in Surrey now kinda, whereas she is still in the Midlands and we don't go to university anywhere near each other.

Also, how do you even start a conversation as such?
'Oh hey, I'm doing a blog project and want to reconnect with an old friend and I've not seen you since before we were teenagers, lets be friends again?'

Not really my style. So we'll see.

Suggestions appreciated.