Sharon, there are no silly questions ~ only silly people, and you came to the right place to find one. :-D

There's no hurry to test your kids. They are all type O. The reason is, in order to be type O, one must possess only O genes (two of them, actually) because O is recessive to any other kind of ABO gene. So neither you nor your husband has anything except O genes to pass to your offspring. That means the kiddles are definitely O.

About the Rhesus type: again, two genes. The possible gene combinations are:

+/+ (Rh positive), +/- (Rh positive), or -/- (Rh negative). You see that the Rh negative gene is just like the O gene: it's recessive. You must have two of them (in other words, none of the "dominant" gene(s))in order to express that characteristic.

The likelihood is that your kids are Rh positive, since both their parents are. However, if both you and your husband are "+/-" AND if both of you contributed that "-" gene to any one of your kids, then he or she would be Rh negative. Maybe a 25% chance of this happening. In that case, you & hubby can also walk around your neighborhood saying "We're heterozygous! We're heterozygous!" [Big word meaning "got one of each." :-)] On second thought, maybe your neighbors wouldn't react warmly to this behavior, but it would sure inspire conversation! ;-D

Rh type is not of paramount importance in following the diets, so I'd say go ahead and assume the kids are Rh positive. No problem waiting till they're older to use the blood type test & find out for sure.

Thanks for your note, and enjoy that single-bloodtype household!