Cranky baby and the mysterious rash

For all of Millie’s adorable smiles, she’s the crankiest baby we’ve had. She can be full and clean, but still scream, holler and push you away. Especially her sister. She’s very strong willed and if you tell her “no,” it just makes her more determined to do whatever. She thinks she’s something when she manages to get into the bathroom to look around. Or when she gets ahold of your phone or remote control. She can lift the lid of the computer. She likes to play in the animal’s water.
Right now she has reason to be cranky. She’s had a rash for about 3 weeks. She looks like a leper. We took her to the doctor initially and she said it was a viral rash. When it got worse, we took her back and the doctor said it was scabies – a mite and highly contagious. I doubt that, though the medicine for it did seem to work for awhile. If it were scabies, we’d all have it, and we don’t. But it’s getting worse again. It was getting better, now it’s worse.
When I was little I had eczema and the doctor said it was hay mites. I got Millie some baby eczema lotion to help with the itch and it helped for awhile, but it didn’t heal. So I don’t know what’s going on. She’s not sleeping well, which may be related and may not be related. Poor baby. She looks like a leper. We’ve rewashed all of her bedding and stuffed animals. I guess we’ll start tracking her food to see if it might be a food allergy. Sometimes she’s pretty miserable with it and sometimes she’s just fine. It’s back on her face, so it looks worse than she feels now.
Pobre baby!