I'm not sure what to make of the separated twins in Chicago and Miami.

It's one of those fascinating stories that come along every so often -- oh our daughters are so similar, our stories are so alike, they must be related.

Biologically, I mean.

Then, DNA testing is done, and lo! it proves they are indeed siblings separated at birth! Or at least likely to be siblings. They think.

DNA testing established that there is an 85 percent probability that they are at least half-sisters. (To reach greater certainty, they would have had to test a parent, an impossibility in this case.) Given all the parallels and their ages, it is most likely that the girls are fraternal twins.

Diana Ramirez was stunned.

"I was in shock," she said. "I was like, `OK, well, now, this is for real.'"

In one sense, it should not have been a complete surprise. The Ramirez family lives two blocks from good friends Tony and Carol Requejo, who adopted a Chinese daughter in 2001. Two-and-a-half years later, the Requejos found that the girl also has a sister living in California--apparently a twin, according to DNA and other evidence.

Something seems weird about the use of DNA there. And this part -- it's in the Miami Herald piece, but mentioned more in detail in the Chicago Trib story, sets my Skeptic Sense a-tingling:

But Funk does not believe their reunion was coincidental.

''I felt all along there were twins,'' Funk said. ``I don't believe in chance. I don't think it was a fluke. I believed beforehand there were two.''

I know that our brains work by creating beliefs (or hypotheses, if you remember your old science fair) and then collecting data to support them.

I think I need to learn more about how DNA matching works.