A Florida couple is suing a fertility clinic after discovering that the wrong man’s sperm was allegedly used to conceive their daughter. According to People, Joshua and Natalie Strong filed the lawsuit in Duval County on Sept. 17 against Brown Fertility Clinic in Jacksonville, along with several members of its medical staff. The couple is accusing the clinic of medical negligence after what they claim was a mix-up that has left their family dealing with consequences they never expected. The Strongs had gone to the Jacksonville clinic for standard In Vitro Fertilization (IVF) treatment. The treatment appeared to be successful, and Natalie gave birth to a healthy baby girl in the spring of 2025. The father suspected something was awry But things quickly took an unexpected turn during one of the baby’s routine medical checks. Blood work showed that their daughter had B-positive blood. That immediately caught Joshua’s attention. He works as a professional nurse and knew that something did not add up. Natalie has O-negative blood, while Joshua has A-negative blood, making a B-positive child genetically impossible based on their blood types. The couple first considered whether there had been a mistake with their own medical records. They had their blood types tested again, while Joshua also checked his medical records from his previous service in the United States military. The results were the same. At that point, the Strongs decided to have a DNA test done. According to the couple, the test confirmed what they had begun to fear: Joshua was not the biological father of their daughter. The couple is now seeking answers through the lawsuit. Their attorneys, Benjamin Ikuta and Rob Marcereau of the Fertility Law Group, have spoken about the emotional toll the alleged mix-up has had on the family. According to Ikuta, Joshua went through medical procedures and paid significant fees in order to become a biological father, only to discover that the child he and Natalie had welcomed was not genetically his. Natalie, meanwhile, is dealing with the knowledge that genetic material from an unidentified man was allegedly used during her IVF treatment without her knowledge or consent. The Strongs say the situation has left them dealing with a range of emotions, including sadness, anger, love, and joy. They still love their daughter deeply, but they now have to think about how they will eventually explain to her why her biological father is someone neither of them knows. The couple said the discovery also took away much of the normal happiness that comes with bringing a newborn home. Instead, they were left with questions about what happened at the clinic and why it happened. The Strongs and their attorneys also claim that Brown Fertility Clinic has not provided an explanation for how the alleged mix-up occurred. The clinic has not publicly responded to the lawsuit. The family is demanding an explanation That is one of the reasons the lawsuit was filed. Beyond seeking financial damages, the family wants the clinic to explain what happened and how genetic material from another man could allegedly have been used in Natalie’s treatment. The Strongs’ attorneys argue that finding out what went wrong is important not just for their family, but for other people who rely on fertility clinics while trying to have children. The case is now moving forward in Duval County, with the alleged IVF mix-up raising questions about how fertility clinics track and handle genetic material and what safeguards are in place to prevent something like this from happening.