Since this phrase has been repeated many, many times by well-meaning people who only want the best for us, and especially for Grace, I'm going to put on my nurse hat for a minute.
Grace has seizures because Grace has a seizure disorder. That is the "why".
Or, as far as we know at this point. And hopefully it will stay that way.
Thus far, we have not uncovered anything else that could be causing her seizures. Her neuroimaging is normal and the very cursory bloodwork we've done has also been normal. I am not entirely ruling out a separate cause for both the facial weakness and the seizures (at this point, we're operating under the belief that the seizures cause the facial weakness, because it makes the most sense, but I can't let my guard down on that because I control the universe and continuing to keep a low-level worry in the background, like the apps that run continually on your phone with some work but not TOO much, will keep it from being anything else.)
This is good.
Most times, when seizures are secondary to another problem, that problem is a very bad one. It is almost always a bad thing to have another reason to have unprovoked seizures (meaning your electrolytes, your blood sugar, and your body temperature are normal, to name a few things, and you have seizures anyway.) The only "good" secondary cause I can think of for seizures would be a minor cortical dysplasia that is easily resected without complication. And even that requires brain surgery, sooo...yeah.
Sometimes, there is a family history of seizures- there is a relatively strong genetic link, so when a family offers that an uncle or a grandparent also had seizures as a child, we nod knowingly and feel unsurprised that the child also has seizures. That is not the case here, as far as we know. That is not the case plenty of times. Only sometimes.
Think of it like diabetes. If you knew someone who's child was diagnosed with diabetes, you might ask, why did they get diabetes? And maybe there is a family history, and that is the "why". Maybe they have a secondary cause, like a pancreatic tumor. Many times, it is just the luck of the draw. They have diabetes because they have diabetes. And six months later, you probably don't wonder, "OK, but why haven't the doctors figured out why she has diabetes??" She has it because she has it. This is very similar.
One way it is very different is that many kids outgrow seizures. Some very quickly. Some take longer. Some are not that lucky and they do not. Of course, we hope hope hope that Gracie will outgrow this, sooner rather than later. And in the meantime, we're looking for any answers we MIGHT find, about how best to treat the seizures so they stop forever. Hopefully we find that answer sooner rather than later, too.