BERKELEY (CBS SF) — A pair of fraternal twin boys will have birthdays years apart after they were born around midnight at a hospital in Berkeley with one coming minutes into Leap Day on Monday, a hospital spokeswoman said.

Miles and Walter Erickson, born to Oakland residents Summer and Ryan, came 11 minutes apart at Sutter Health’s Alta Bates Summit Medical Center in Berkeley, hospital spokeswoman Carolyn Kemp said.

Miles was born at 11:58 p.m. Sunday and Walter was born at 12:09 a.m. Monday, meaning his Feb. 29 birthday only comes once every four years, Kemp said.

The twins were born premature at 26 weeks, meaning they will remain at the hospital for a few more months while they grow and gain strength, Kemp said.

Miles weighed 2 pounds, 2.6 ounces at birth while Walter weighed 2 pounds, 4.7 ounces, she said.

“The boys are doing well for their age” and are interested in eating, Kemp said. “Now their job is to grow and get healthy.”

Ryan and Summer, who will remain at the hospital for another day or so, also have a 4-year-old son Bruce.

“Mom and dad are over the moon,” Kemp said. “It’s the most unique of days and the most unique of births. They’re thrilled.”

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