Here's what I would do:
Take a photo of the rash. Put a coin or ruler next to the rash for size reference. Then get to the doctor and get Doxycycline. Almost any MD should be willing to give at least a few weeks of doxy for a bull's-eye rash. Then look for an LLMD or Naturopathic physician to work with to make sure the infection is nipped in the bud and not just slowed down for a few weeks. Also, keep the immune system strong - garlic is a good thing to eat because it boosts the immune system and has sulfur in it to help the body to eliminate the lyme die off toxins. The tick that bit them (if it was saved) can be sent in to IGeneX for testing to find out if it is infected with Lyme.
You might also want to print out the thread near the top of the forum called, "The Basics - Newbies, Check this out!" and give that to them also.
I hope this helps - take care,
Chronic Lyme Disease, Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut issues (dysmotility, non-specific inflammation), UCTD ("Secondary Lupus-Like Syndrome"), Osteoporosis, Pancytopenia, chronic malabsorption/malnutrition, etc.; G-Tube; Currently TPN-dependent.
Meds: Zofran, Pulmicort, Heparin (to flush PICC line), Claritin, Colloidal Silver (used topically), IV Milk Thistle, probiotics.