Pal of mine

Once we were strangers, you and I
Those people my mother told me to never talk to
But we’ve upgraded to friends
I don’t know when it happened or how
For some I remember the meeting
And then the slow progression from acquaintance
To yeah old pal of mine
There are those who never went this far
Stayed only as a mere knowing of someone
But I’m mighty glad this wasn’t you
For I’m very fond of this familiarity of ours.