I think a part of KayTar's issues are SPD. Josh and I did spent the morning doing additional research, and we found that she can be affected across the board, in both hyper and hypo sensitivities. We went through a checklist and the number of signs she exhibits is unreal.
This morning we let her play with dry oatmeal (pouring, scooping, throwing) in her highchair and she really enjoyed herself. Josh thought it would be fun to let her play in some shaving cream, too, so he squirted it onto the tray. KayTar touched it, immediately grunted and raised her hands to us to say "Get it off!" and before we could wipe her down, she gagged and threw up. Twice. It was the strangest thing I have ever seen. She vomiting because of a sensation on her hands. I didn't know that was possible.
I know this doesn't explain the seizures or the loss of words, but it does give us another piece of the puzzle. We are going to try it again later to get it on video to show the pediatrician, neurologist, and evaluation team. I am also going to call Monday and see if we can push her sensory evaluation to the front of the line, instead of one of the last things to be evaluated.