Hello Betsey, and welcome to Anxiety Zone... My name is Chuck, and I am one of the Global Moderators here on the site.
You are now a member of our community, where you will find support and advice from other members in similar situations. It's always nice to find someone else who understands, and to know you're not alone.
We have sections in the forum that address specific concerns, so feel free to post or start a new topic in the section that best fits your situation. Feel free to explore the rest of the forum. You may find the other topics helpful, and you may be able to offer advice or support to someone else.
We also have a chat room for members over the age of 18. Once you have made three meaningful posts, you will be allowed access to the chat room.
Betsey, part of the support you are seeking, lies within your own post. No one has any control as to whether a child will develop autism or not. That is completely, 100%, out of our hands. You said that if your youngest were to develop autism, you would do all that you could for your child, and I commend you for that.
I highly suggest that you do all that you can to treat/get treatment for your anxiety disorder. And I find that the Serenity Prayer provides a lot of wisdom: "God, grant me the serenity to accept the things I cannot change, courage to change the things I can, and the wisdom to know that difference."
Again, welcome to Anxiety Zone. The very best to you, Betsey!... Chuck