Mark MacDonald grew up knowing he was adopted after his biological mum had him at just 16, but he says he "never really gave it much thought".
In fact, Mark never bothered to look into his lineage until he and his wife Tina discovered they weren't able to safely conceive a child.
After receiving the devastating news, the 49-year-old professor from Portland, Oregon, began searching for his birth parents, PEOPLE reports.
