You may think that your kids are one in a million, but a Texas woman just gave birth to two sets of identical twins on the same day--a one in 70 million occurrence. Thirty-six-year-old Tressa Montalvo was not on any fertility drugs, saying: "We planned the pregnancy. I guess we just succeeded a little too much." The caesarean sets of sets of twins--Ace and Blaine, followed by Cash and Dylan--each had their own placenta.. Tressa explained: "We tried to stick to the A-B-C-D theme when naming them. We didn't expect it, we were trying for just one and we were blessed with four."