By Jane Nambi

36-year-old Tressa Montalvo from Texas together with her husband welcomed two sets of identical twins on Valentines day much to their delight.

All the couple wanted was give their first-born son a little sister or brother but instead, he got four brothers. The children were conceived at the same time at The Woman’s Hospital of Texas in Houston.

Ace and Blaine shared one placenta, while Cash and Dylan shared another. Talking about the names of their children, Montalvo said they stuck to the alphabetical order. “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.”

Montalvo and her husband, Manuel Montalvo Jr., 43, thought they were having twins until their doctor detected a third fetal heartbeat and when they were referred to a maternal fetal medicine specialist, Dr. Brian Kirshon, they found a fourth heartbeat.

“We couldn’t have been more surprised when Dr. Kirshon told us we were having four babies and that they were two sets of twins,” Manuel Montalvo said in the statement. “We were trying for one little brother or sister for our two-and-a-half year old son, Memphis.”

The odds of having two sets at the same time, according to Dr. James Grifo, director of the NYU Fertility Center is slim. “The chance of this outcome is approximately one in 10,000,” Grifo said of two embryos splitting after IVF. “This could also occur in a natural conception, but the chance of that is much [rarer].”

“No fertility drugs were used. We planned the pregnancy – I guess we just succeeded a little too much!”

The children were born by C-section at 31 weeks and weighed between 3 pounds, 15 ounces and 2 pounds, 15 ounces.