At just 12 days old, a sweet little baby girl received open heart surgery.

Miraculously, this baby girl pulled through like a champ and grew up to be Giselle Ramirez.

"She was born with Transposition of the Great Arteries, which means her arteries, instead of being crossed, were born parallel," said Liliana Ramirez, Giselle's mother.

Per the American Heart Association, TGA is when two of the main arteries are carrying blood away from the heart. For example, a normal blood pattern would carry blood in a cycle: body-heart-lungs-heart body.

Giselle is now 6 years old and was on her way to first grade.

Just by seeing her, you would never expect she had gone through such a strenuous heart surgery at such an early age.

But everything changed for Giselle on Tuesday, Aug. 22, 2017, while getting a simple dental procedure done.

"We were thinking it was going to be like any other in-and-out procedure. She had gotten dental work done before, and we get it done at the hospital because of her heart condition," said Liliana.

A simple procedure turned out to be a nightmare for Giselle’s mother.

"The dentist came out and told us that everything had gone good in his procedure (filling her tooth) but unfortunately, she had a cardiac issue," said Liliana.

Right away, Giselle was admitted to the Cardiovascular Intensive Care Unit at Phoenix Children's Hospital.

During all this, Liliana hadn't seen her daughter in hours and wasn't quite aware of exactly what was going on with her little girl.

"A few hours passed by when they came (doctors), and that's when they came to tell me, 'Oh, we were able to stabilize her,' and I was just so confused," said Liliana.

Little did she know, her daughter was about to be transferred to the cath lab (an examination room to examine arteries of the heart), where her daughter went into cardiac arrest. Moments later, Giselle suffered a massive heart attack.

Dr. Daniel A. Velez, MD of PCH, who attended Giselle, confirmed over a phone call that she went into cardiac arrest, had no heartbeat for 60 minutes and him and his team had been giving issuing chest compressions to stabilize her.

He also confirms that Giselle had to be rushed to the operating room immediately to open her coronary arteries.

Thankfully, Giselle pulled through the surgery, but there was still precaution.

Dr. Velez mentioned that her left coronary was getting little oxygen, and her right one was not getting any oxygen.

"When I went into to see her she was on a ton of medicine, a machine that is called extracorporeal membrane oxygenation (an equipment that acts like a lung to deliver oxygen to the blood), that was basically doing her heart function for her and a ventilator, “said Liliana.

Through it all, Liliana says she is very thankful that this incident happened to her daughter during the dental procedure. She says doctors told her it could have happened anywhere and at anytime.

Being a single mother, and having to take hold of the situation, Liliana knew she had to be strong and not let her daughter see her break down.

Giselle was discharged from PCH Sept. 12, 2017 and is now at home recovering with the help of Liliana's family.

"She can't be held under her arms, she has to be very careful because her chest is still healing," said Liliana.

Sweet Giselle can't really do what many 6-year-olds should be doing.

Giselle still can't come to terms with what happened to her on that Tuesday.

Reporter: "Do you understand it now?"

Giselle: "Not really."

Now, Giselle is going through physical therapy and requires long-term medications.

It still blows the doctors away that through it all, Giselle suffered no brain damage.

This is little bright star isn't letting her surgery stop her from smiling at all.

In fact, she is excited to hopefully get cleared from doctors to go back to school and to dance.

Dr. Velez says that indeed, "she is truly a miracle."

If you would like to know more about Giselle and how you can help the family, you can go their GoFundMe Page.