However, to answer your question. I did not remember the answer when you first asked. So I went to research it. And then forgot to get back to you.
We do not know the specific date of Yeesha's birth. It is possible that we might discover it at some future point. One never knows.
Which leads me to come up with a standard answer for situations such as this: "I can't remember yesterday. I know even less about tomorrow."
I have to write that down somewhere before I forget that, too.