When a New Jersey couple was having trouble conceiving a child, they went to a fertility clinic and decided to do artificial insemination through in vitro fertilization (IVF).

In 2012, Kristina and Drew Wasilewski spent nearly $500,000 at the Institute for Reproductive Medicine and Science at Saint Barnabas in Livingston, N.J., for the complex procedure.

The procedure was a success, but as time passed, and their daughter aged, the Caucasian couple noticed she was developing Asian features.

That’s when a DNA test determined that Kristina was the only biological parent to the 2 year old.

On Aug. 28, the now divorced couple filed a lawsuit against the fertility clinic, asking the hospital to release documents so they could determine who the girl’s biological father is.

"Negligence, recklessness, you call [it] what you want,” David Mazie, the lawyer representing the pair, told CNN. “This should never ever happen.”

The clinic is not commenting on the case because it’s in litigation, according to CNN.

"They have a right to know who he is,” said Mazie. “They have a right to know his genetic history.”

In the lawsuit, the clinic does claim that “the plaintiff’s sperm was in fact used for the IVF and/or that an extramarital affair led to the minor plaintiff’s birth.”

The girl, now aged 6, has a blood disorder that her non-biological father and mother don’t carry.

The judge in the lawsuit does state that the child has a right to know who her father is and whether she is “vulnerable to any genetic diseases.”