Hello, my name is Dr. Farwell. Sorry to hear about your predicament with Skip.
At least it's a very fixable one;)
First, make sure to get Skip onto some sort of monthly flea prevention such as Advantage or Frontline.
Does he have live fleas on him now?
As for your family members, I would let them know. Have them check their pets and ask if they are getting bitten inside their homes.
Once all the affected pets are on monthly preventative, home treatments are recommended.
If infestations are mild, your family will probably be able to get away with simple areal treatments. There is a powder labeled Flea Busters which basically dehydrates the fleas. It's applied to carpets, couches, etc..... allowed to sit, then vacuumed up.
Also washing any and all bedding (dogs/human) and throw rugs helps. Obviously a home with hard wood is more easily managed with fleas.
Some heavy flea infestations require bombings done by a professional exterminator service, however if your dog only visited your family members it may not be that severe.
Whatever method is chosen should be done once and repeated in 2 weeks, this gets the juvenille fleas before they are able to produce more eggs.
Hopefully this helps. Please feel free to respond with any further questions.