20 Month Old Has Red Bumps On Bottom, Legs And

20 month old has red bumps on bottom, legs and now arms - initially thought maybe it was hand/foot/mouth when just on tops of feet, back of knees and bottom - but never on the soles of hands or feet so rules that out. Now the little red bumps are spreading up her arms and all up and down the front of her legs.
No fever - drinking and eating fine - life seems to be as normal and pleasant as can be for a teething 20 month old!
Could this simply be something like chigger bites or something worse?