You guys ever heard of that fanon where Strauss was one of the people Rossi slept with when he was sleeping around with everyone?
Well look at the pictures of her son, and compare with young Rossi!!!!
http://criminalxminds.livejournal.com/1851610.html?thread=15452378#t15452378 What are you doing show? The girls looked like her husband, but the boy is like Rossi jr, the smirk, the eyes, the slight eyebags, even the cheek and chin line (more pronounced in the family group photo)