What Does First and Second Act Mean?

On Matt's side of the family, most of the immediate members, coincidentally ended up spelling a word from their initials. So there are some M.A.T's, B.A.T's, S.A.T etc. So when Matt and I got married he thought it was pretty funny that they were adding an A.C.T (Amber Chantel Thompson). He knew I fit right into the family because my initials now spelled something. So when I was pregnant and we were choosing a name he always needed to spell out the initials. When we chose Alyssa's name he thought it was perfect that he would have a first and second Act and i thought it was pretty funny that he would come up with something ingenious like that.

So here we are: The First and Second Act.