I'm confused. I am helping my 1/2 sister with her genealogy DNA matches to figure out who her biological father is. Here is what I have found- a 2nd cousin whose mother was a Lamb, father was a Lamb & mother a Ross. There is a 3rd cousin who is also in the Lamb family. That means the 2nd & 3rd cousin to my 1/2 sister are 2nd cousins to each other correct? I believe (99% sure) their respective grandparents were Lamb siblings.
Am I correct that I now have to search the Ross family to find her father?