Photo: @roberts.supertwins/Rebecca Roberts

A new mom in England is breathing a sigh of relief after a harrowing pregnancy allowed her to give birth to two siblings who were conceived weeks apart.
“My initial reaction was, ‘How had I missed the second twin?’ " Roberts' OBGYN, Dr. David Walker at Royal United Hospital in Bath, toldGood Morning America. “And following this [I] was slightly relieved that it was not my mistake but a quite extraordinary pregnancy.”
Superfetation occurs when an egg is released from a woman’s ovary after she may be pregnant already, and implants alongside the first embryo in the uterus some time later.
“It was really, really shocking to be toldthere were two babies instead of one,” Roberts, 39, toldGMA. “Then they told me there was a three-week size difference between the two babies that the doctors couldn’t understand.”
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But when her mothergave birth at 33 weeks gestationwith Noah, Rosalie was delivered at 30 weeks before spending three months in the neonatal intensive care unit. Roberts was induced because her daughter had stopped growing, due to an issue with her umbilical cord. Her placenta also “never really grew properly,” according to her mother.
“What came after getting pregnant was just such incredible hard work,” she also said. “It wasn’t all happy and rainbows like you expect a pregnancy to be. It was quite scary.”
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Rosalie left the hospital to come home just afterChristmas, and Roberts said that she’s already catching up to Noah in terms of her growth.
Theirbond is something special, too. “When we lay them down next to each other, it’s like they instantly know and they reach out and touch each other’s faces and it’s just the most beautiful thing,” she said. “Twins have an amazing bond anyways but the story between these two, when they’re old enough to find out, they’ll feel even more special.”
Roberts said she and husband Rhys"were trying for ages to” conceivewith no luck before the twins, and that they were “worth waiting for.”
“They’re my super twins,” the proud mother of two toldGMA. “Every day I look at them and think, ‘Wow, I’m so lucky.’ "
source: people.com