I want to say before I start this entry that I am not a doctor, obviously, and I am using medical ideas to write this that I have remembered along the way. Please don't take them for hard facts, as they could be wrong! What I'm trying to do here is give my thoughts based on what I've read and heard, which is I think what we all try to do with figuring out this autism bit!
That said, my theory #2 of what caused Janey's autism is that autism is an autoimmune disease, and our family is for some reason heavily prone to autoimmune diseases. As I understand it, an autoimmune disease is one in which the body's own defense mechanisms get overactive and attack the body they are supposed to be protecting. The idea is that something triggers the body to start attacking the brain at some point, causing autism. It could be some little sickness we can't even remember the child having, or some other trigger that is impossible to figure out.
Our family tree is full of examples of diseases that are at least in part autoimmune. I have a pretty much non-functioning thyroid and have to take large doses of thyroid replacement every day. I also have asthma. When I was pregnant with 2 of my 3 kids, I had pre-eclampsia, which is thought to be another AID (auto-immune disorder, so I don't have to keep writing it!) Tony is an insulin-dependent diabetic, a type that is kind of a cross between type one and type 2. Freddy has asthma like me. My mother has Raynaud's Disease. My sister, my mother, Freddy and myself all have pretty severe seasonal allergies. My sister had thyroid cancer. My uncle and grandmother had or have disfunctional thyroids, like myself. Almost everyone in Tony's family has the same kind of diabetes he does---his brothers, his father and many aunts and uncles and cousins. The list could go on and on. We are poster kids for AID.
One, someplace, I read that another sign of being prone to AID is when the MMR vaccine doesn't take as a child. Both my sister Carrie and I were tested when we were at child-bearing ages, and were found to be not immune to rubella, and had to have another shot. Our immune system fought off even the vaccine dose as kids, and didn't therefore get the immunity.
The AID-autism connection just makes sense to me. You aren't born with AID. Something triggers them. That would explain why kids develop autism as they get exposed to more things in the environment. Some people are pre-disposed to AID---not every kid is going to be triggered to be autistic.
A weird thing that also seems like a connection to me is how rarely Janey gets sick. She doesn't get the colds or flus or viruses that go through her classes. She's missed almost no school days due to illness in years. William, who was originally also thought to be on the spectrum, is the same way. Freddy gets everything that goes down the pike and more, so it's not just a family trait to not get sick. I think Janey's immune system is overactive. She gets rid of any illness that comes around, and does so overactively. I can see how at one point, something might have triggered her body to go all out on attack, and mistakenly went for her brain, too.
As with the pregnancy/fever/flu theory, the AID theory could easily explain Janey's autism. I wish it were the last thing that could, but there's more! #3 in this series is coming soon.