Her condition occurs in an estimated 5.5 times in one million live births.
Virsaviya Borun, six, was born with her heart and intestines outside her chest and abdomen.
When her mother, Ms Dari Borun, was pregnant, the doctors said the baby would not survive, Mail Online reported.
But little Virsaviya, a Russia native, has defied the odds by surviving so long. Her heart, the size of a fist, can be seen beating against her abdominal area, protected by a thin layer of skin.
She has no abdominal muscles or diaphragm.
Virsaviya's condition is caused by Pentalogy of Cantrell - a rare congenital condition. The condition often requires surgery. It could be fatal if not treated.
"I like to draw Jesus, ponies and angels," the girl told NBC Miami. "I don't go to the school and I don't go to the ballet but I want to do it at home.
"My heart is right here. It's outside of my chest and I really love my mum, she's always touching my heart because she likes it."
Early this year, Ms Borun, who has been raising her daughter by herself, found a doctor in Boston who was willing to treat her daughter.
But the medical team there said Virsaviya cannot undergo surgery now because of high blood pressure in her pulmonary aorta.
She will be re-evaluated in two years.
They have moved from Boston to Florida because Virsaviya, who also goes by the biblical name Bathsheba, cannot cope with the cold climate.
Said Ms Borun: "I don't have a family in the US. It's just me and Virsaviya, but now I feel like I have a family because a lot of people care about us. They want to help."
They have launched a fund-raising page on Youcaring.com called Bathsheba's Heart.So far they have raised more than US$16,000 (S$22,400) with a goal of US$20,000.