"Category" sibsets you know?

I’ve seen them discussed on Nameberry, but had never encountered one until last week. Sibset names that follow a strict naming convention by category. I just met a woman who said her children are named [name]Utah[/name], [name]Montana[/name] and [name]Nevada[/name]. I assumed [name]Montana[/name] was a girl, though I don’t know for sure.

So what sibsets do you know that follow this pattern? I always assumed there were lots of little sisters out there named [name]Rose[/name], [name]Lily[/name] and [name]Violet[/name], but it never occurred to me that there might also be sibs that share state, color or animal names. Tell which ones you know and your opinion on choosing names based on such strict (and eclectic) rules.