Half birthday...

Really random thought.
Towards the end of this long day I looked at my phone.
To see how much longer till the work day was over really.
Not that I actually have a set 'end time' of the day!
Anyway, I saw on my phone 'January 23'.
And said to my friend, 'it's my half birthday'.
To which she replied, 'I don't even know when my half birthday is'.
So, random assignment for the day- figure out when your half birthday is.
V- yours is August 21.