Mystery Rash

On Saturday (15th) I noticed a few spots on Asher's leg. On Sunday morning it was clear there was a rash starting. On and behind her knees they were bigger and spaced apart.
But on her feet they were tiny and close together. Also doing similar thing on the bottom of her leg.

Most AEDs (Anti-Epileptic Drugs) have instructions to contact your doctor immediately if a rash appears and because Asher had an increase in dose on Thursday - I phoned the hospital to just keep in touch with them. They were happy to wait and see what happened but said I should call again if it got worse.
On Monday morning (17th) it had spread to her arms and a little bit of her body so I phoned our local doc and they said I could bring her in. They phoned her specialist and described the rash (it helped having a doctor describe it to a doctor) and he asked for some bloods and suggested we wait for 48 hours and just monitor it.
I was happy with this decision. If it's not the AED then we don't want to stop her medication "just in case" as it may be the one that works to control her seizures.
The nurse and doctor at our local rooms were not comfortable taking her blood themselves as she does have very small veins and they have not drawn blood from a young child in quite a while. So we headed off to the lab in town.

By the time we had her bloods done after lunch the rash had gotten worse and I got a bit of a fright when I tried to feed her and she would not drink. I noticed two sores in the middle of her tongue and was concerned that it would just spread into her mouth and stop her eating. So I phoned the hospital from the lab and asked if I could rather just come there rather than heading all the way home and then possibly having to come back. They agreed that it was safer and we headed over to CAA (Child Acute Assessment).
Thankfully when I tried to feed her again later she was able to drink and have something to eat and that made me feel more relaxed about heading home. Her neurologist popped in to see her as well and the plan was made that if her bloods came back normal we could head home. If not we would discuss things again. Thankfully the blood results were good. The doctor also gave me a spray for her mouth so that if it did spread into her mouth and stop her eating later or tomorrow - I had something to help her with the pain so that she would at least be able to continue to drink and eat. We eventually arrived home at 6:30, so I was rather tired from a long and emotional day.
Tuesday saw the rash even worse. Almost solidly covering her legs and arms. Thankfully it didn't worry her mouth any more and the spots from Monday on her tongue had cleared. Through this all she has had no other symptoms.
No fever, runny nose or cough and no problems in her ears or throat. It has also not appeared to be itchy at all as she has not scratched it either (another blessing).
It actually intensified on her body and started spreading to her face through the morning but she continued to be well in herself which I was very thankful for.
On Wednesday when she woke it looked like it was almost gone. By the end of the day it had not come back and I was very thankful that it was over. It still remains a bit of a mystery to us all.