"Hey, it's Mom...you know, the one who gave birth to you? I know you are
I just wanted to remind you that Friday is my birthday and I know that you are
It's a big one for me, you only turn 31 once, so I didn't want you to feel bad if you forgot to call. Yes, I know you are a math whiz but I promise, I had you when I was 12.
Love you, Bye!"