Pox?

[Gumps]

My dd nearly 2 has a bizarre line of spots on her back. They are in a straight line on her back and then go over her shoulder to her chest. There are also a couple of clusters on her front but none anywhere else. They are red with a tiny head.
I've put a pic on my page. She is no 3 but none of mine have had the pox. Or maybe in my failure to diagnose I have missed it?
We are supposed to be going to a rainy BBQ today so any amateur diagnosis would be much appreciated.

Picture is so small, but they look swollen around the red point, CP not like that ime. I hate to say it, but linear pattern fits bed bugs. Have you travelled anywhere lately.

Chicken pox are usually turned into fluid filled blisters really quick and spread fast. On phone so can't see pic.

Mmmn have just googled bed bugs and stripped cot, taken out matress and wiped the whole thing down. White cot and plastic backed mattress so presuming g would be obvious to see? Have stripped all bed linen to hot wash just incase...
Has def spread as more on chest today but not at the rate I have heard pox does. She is also quite rashy elsewhere but no temp or scratching and is pretty happy.
Hmm ...