Amy,
I just had this experience of self realization after 50 years. I have three kids about that age. I am taking it slow and have only informed my wife and one other close friend. I expect to talk to my kids but it may be a while yet.
These are my experiences. We are all in different worlds. But I can say, the world our kids are growing up in is so different than even 10 years ago. However, you are their parent. If I tell my kids first, I'll let you know how it went.
With warmth,
Joanna