Need help finding romance book

Hello everybody! I was wondering if anybody can help me find a romance book I read a couple of years ago. I, unfortunately, don't remember any names or how the book ended but I do remember the plot. It starts with a man who recently lost his wife and gets a call from their fertility clinic to inform him that the clinic made a mistake or there was a mix up and he has a biological child, a son, with an different woman. After finding out he has a son he finds the mother but she had her mind set on raising her son as a single mother. They were both trying to understand the whole situation in regards to their son. I apologize for the lack of information, and any suggestions would be greatly appreciated! Thank you!