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These twins were born in two different years — here's how

A California mom ended 2017 by welcoming one bundle of joy and then kicked off 2018 by giving birth to his twin sister.
/ Source: TODAY

A California mom ended 2017 by welcoming one bundle of joy and then kicked off 2018 by giving birth to his twin sister.

Joaquin Jr. Ontiveros now has a lifetime of "I'm a year older" jokes for his sister after being born at 11:58 p.m. on New Year's Eve, followed by the birth of Aitana de Jesus Ontiveros at 12:16 a.m. on New Year's Day at Delano Regional Medical Center in Delano, California.

The original due date for mom Maria Esperanza Flores Rios was Jan. 27, so she was happy they both were born healthy after being four weeks premature, according to NBC affiliate KGET.

Joaquin is 18 inches long, weighing 5 pounds, 9 ounces, while Aitana is 16 1/2 inches long and weighing 4 pounds, 10 ounces.

"I've been in the practice for almost 30 plus years," Dr. Seyed Tamjidi, who delivered the babies, told KGET. "I've never had the opportunity to do anything like that before."

Aitana was also the first baby born at the hospital in 2018, and per hospital tradition the family was gifted $3,000 in baby supplies that will now be used for two.

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