"She's going to be a normal child. She'll go to kindergarten with her friends. That is incredibly rare," Dr. Darrell Cass said.
It's a special day when any baby enters the world for the first time, let alone twice.
That's only the beginning of the story for little Lynlee, who was afflicted with a tumor while she was in utero.
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Margaret Boemer of Plano, Texas was 16 weeks pregnant when doctors discovered an abnormal tumor on her baby during a routine ultrasound.
Upon further diagnosis, doctors confirmed her fetus had a sacrococcygeal teratoma, or a tumor growing from her tailbone.
"They are extremely rare, but it is the most common tumor we treat as surgeons on a newborn," said Dr. Darrell Cass, a pediatric surgeon at the Texas Children's Fetal Center. "Sometimes these tumors can be well tolerated in the fetus [but] her heart showed signs of starting to fail."
Cass explained that as the tumor grew on the baby, it would compete with the heart, and try to redirect circulation to the tumor instead of through the body for normal development.
At 16-weeks developed, little Lynlee's heart was pumping overtime, and doctors were worried that she wouldn't survive the full term.
Boemer had a complicated pregnancy from the beginning. She had originally been carrying twins, until one died before her second trimester.
Determined to make sure her baby survived, Boemer reached out to different hospitals until Texas Children's agreed to give her case a try.
They decided to continue with fetal surgery, where, at 23 weeks and five days pregnant, surgeons would remove the fetus' tumor by taking her out of the womb through an incision in her mother's uterus as both the mother and the fetus were under general anesthesia. After the tumor was removed, surgeons would carefully place little Lynlee back in her mother's womb, where she would continue growing until birth.
Cass told InsideEdition.com that while the surgery has been done before, it has only been successful twice previously.
"It's been unsuccessful many times," he clarified. "A lot can go wrong and the fetus can die after, or during the surgery."
The most likely possibility was that the fetus' heart could stop while surgeons were operating, which did happen in Lynlee's case, but top cardiologists were able to save her mid-surgery.
Cass explained that the fetus could continue bleeding after the surgery, and pass away the following day. Or, amniotic fluid would leak out of the uterus, which could force preterm labor.
But, "we've just been really fortunate," Cass told InsideEdition.com. "Little Lynlee had zero complications and she recovered perfectly."
Boemer was on bedrest for the rest of her pregnancy, until June 6, when little Lynlee emerged from the womb for the second time in her life.
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Eight days after her birth, Lynlee underwent another surgery to remove the remainder of the tumor.
Now, doctors say the 4-month-old is doing great.
"She's completely cured," Cass said. "She's going to be a normal child. She'll go to kindergarten with her friends. That is incredibly rare."
Her mom said, "God gave us this gift, and we're thankful we could give her life."
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