A Florida couple says a fertility clinic used another man’s sperm to create their daughter’s embryo, shattering their hopes of becoming biological parents after DNA testing revealed the child’s paternity.
Joshua and Natalie Strong allege that officials at Brown Fertility in Jacksonville, Fla., including Medical Director Dr. Samuel Brown and 10 other defendants, were responsible for the mix-up that left a stranger as the biological father of their 1-year-old daughter, according to a lawsuit obtained by The Post.
“They trusted Brown Fertility, as well as its founder and owner, Samuel E. Brown, M.D., with the family they hoped to build. That trust was betrayed,” the couple said in the lawsuit filed Thursday in Duval County Circuit Court.
“The Strongs are now raising a daughter whose paternity test confirms that another man, not Joshua, fathered her.”
The couple had turned to Brown Fertility in hopes of having children of their own. Instead, they say they were devastated when testing revealed that Joshua was not their daughter’s biological father.
“It’s a daily struggle with the emotional aspect of it because you do have sadness and anger in the same day, you also have joy and love,” Joshua Strong told Jacksonville’s First Coast News.
Because Joshua had undergone a vasectomy earlier in life, he required an invasive surgical sperm-retrieval procedure. The procedure produced four vials of sperm.
The couple paid Brown Fertility “tens of thousands of dollars” for treatment. The clinic was named one of “America’s Best Fertility Clinics” in 2025.
The vials were provided to Brown Fertility with specific instructions: the clinic was to use Joshua’s sperm to fertilize Natalie’s oocytes and later transfer the resulting embryos to her.
Natalie gave birth to a baby girl in June 2025. But, the couple says, signs of a problem emerged almost immediately.
“Within the first day of life, routine newborn blood typing produced a result that did not fit,” the lawsuit alleges. “The Strongs’ daughter typed Blood Type B Positive. That result is biologically impossible given Natalie’s blood type, O Negative, and Joshua’s blood type, A Negative.”
Further DNA testing determined that there was a 0% probability Joshua was the baby’s father.
“It took away the euphoria of having a baby,” Natalie told the outlet. “It was my first child, I was in heaven. It was the best day of my life and then when that hit us, it took all the happiness away, which we should have had for a very long time.”
The couple says they informed the clinic about the test results but received no explanation.
“Despite irrefutable DNA evidence, Brown Fertility and Dr. Brown have refused to admit what they did, refused to account for Joshua’s missing sperm, and refused to take responsibility,” the lawsuit states.
This was the second time the couple had undergone the IVF process at the clinic. Their first attempt ended in a miscarriage about one month into the pregnancy in mid-2024.
The Strongs also allege that Brown Fertility used the wrong sperm during that first pregnancy and that the whereabouts of Joshua’s sperm were eventually brought to light.
According to the lawsuit, the clinic has not explained what happened to Joshua’s sperm—whether it was misplaced, discarded or used without the couple’s knowledge to create another couple’s embryo.
“The Strongs do not know whether Joshua has biological children, fathered without his knowledge, being raised today by other Brown Fertility patients who have no idea,” the lawsuit says.
The Strongs are seeking more than $50,000 in damages and a jury trial.
“Natalie suffers the daily knowledge that her body was used, twice, to carry a stranger’s child,” the lawsuit says.
“Joshua suffers the daily knowledge that the daughter he is raising bears no biological connection to him, the loss of the irreplaceable genetic future he believed he was building with his wife, and the unending question of what became of his cryopreserved sperm.”
