“我要做爸爸了”用英语怎么说?然后请假条怎么写?

I'm going to be a father/daddy/dad
Dear xxx
My wife's due date is on .(预产期）.It's very exciting and my wife is a little bit nervous.I really hope i can stay with her in this special period of time.
I will appreciated that if i could take xxx days off to get ready for the baby's arrival.（如果是工作方面的,一般发email的时候还应该把一些工作交代一下,以确保你走人以后没事）
Thank you very much
sincerely
xxx