Lynlee's mother, Margaret Boemer, was 16 weeks pregnant when she was told that her daughter would need treatment before her due date, as doctors had found a tumour on the child's tailbone.
'They saw something on the scan, and the doctor came in and told us that there was something seriously wrong with our baby and that she had a sacrococcygeal teratoma,' Margaret, from Plano, Texas, explained.
'And it was very shocking and scary, because we didn't know what that long word meant or what diagnosis that would bring.'
Dr. Darrell Cass, co-director of Texas Children’s Fetal Centre and associate professor of surgery, pediatrics and obstetrics and gynecology at Baylor College Medicine, told CNN that teratoma is the most common type of tumour in babies, although it's still 'pretty rare', affecting every one in 30-70,000 cases.
In some instances, treatment can be delayed until after the baby arrives, but because Lynlee's tumour was competing with her body for blood flow, the decision was taken to act sooner.
The procedure to remove her tumour took place 12 weeks before her 'second' birth through Caesarean section. She weighed just 1lb 3oz at the time.
'The part on the foetus we do very, very quickly. It’s only 20 minutes or so on the actual fetus,' Dr Cass added.
'Most of the time was taken up cutting into the uterus. Once the surgeons reached the baby she was lifted so she was "hanging out in the air."'
'Essentially, the foetus is outside, like completely out, all the amniotic fluid falls out, it’s actually fairly dramatic.'
'It's kind of a miracle you're able to open the uterus like that and seal it all back and the whole thing works.'
Despite the risks associated, Margaret said that she knew that the surgery was her daughter's best possible shot at survival.
'Lynlee didn’t have much of a chance. At 23 weeks, the tumour was shutting her heart down and causing her to go into cardiac failure, so it was a choice of allowing the tumour to take over her body or giving her a chance at life.'
'It was an easy decision for us: We wanted to give her life.'