Question about stomach ailment

[EKS]

My 5 yo had a stomach thing last Thursday and was pretty much recovered on Friday. Just last night my 11 yo had what appeared to be the same thing. I'm surprised it took my 11 yo so long to come down with the thing. They each were at aikido class (at the same studio) 12-24 hours before the vomiting started.

So--do you think it is more likely that the younger gave it to the older (I tried to keep them separated during younger's illness) or that they somehow each got it from aikido on different days? Or some other way?

I was reading that the incubation period for these things is usually 4-48 hours.

I know I'm overanalyzing this but I really don't want to get this thing and I thought we were out of the woods until last night.:eek:

Thanks!

[Jenny in Atl]

That 4-48hrs thing is a myth. Our family got a stomach bug over the holidays, yes lovely timing :eek:. Anyway, youngest dd got sick Monday night (she was sick on and off most of the rest of the week - better then worse, etc. Then I became sick four days later, and finally my husband, eight days from when my youngest first became sick, even after he had drunk out of one of her cups the first night she throw-up. Oldest dd did not get sick at all. So we had a four day and a six-day period between. Poor hubby got it Christmas night just as we were ready to sit down to roast beef and Yorkshire pudding. It was not a fun ride home from Grandma's :(