I don't think I'd be so quick to rule out fleas or bed bugs just because of the appearance of the bites. They can look quite different on different people, different photos, etc.
And you don't have to be "unclean" to have either.
Fleas can be tough to spot if they are in your carpeting. I visited a friend once, and I was getting eaten alive, especially on my feet, ankles, and bottoms of my legs, and I never saw anything. Finally, after some intense watching and looking deep into the carpet, I saw the little buggers. She was infested. And had no pets. It can happen.
Also, I think I'd do a good search for bed bugs, too, before ruling them out. As others have noted, they have made quite a comeback recently. Especially if you or any family member has stayed somewhere other than your home within the last 6 months or so, namely a hotel, but even a friend or family members house. Bed bugs are extremely easy to transport, and very difficult to find because they are nocturnal and they hide well. Inspect the edging of your mattresses, around your bedframe and rails, around any curtains in bedrooms, under the mattress, between the boxspring and mattress, etc. and look for little like blood spots or fecal matter. If you see any of these telltale signs, you might be infested. Check your daughters too.
Anyhow, good luck finding your culprit. I'm sure this is quite an annoying problem.