Ok, here is what we were told.  It appears that his knee has serous fluid which they tell me is normal after surgery.  Most of the time the body absorbs it and everything is fine.  It is a little red, however, it is not warm to the touch and they did not feel that it looked infected.  From what I gathered, it is a waiting game to see if the fluid absorbs or not.  So, I am set to go back in 2 weeks.  I did find this so I could understand it a little better.  
 
"A seroma is a pocket of clear serous fluid that sometimes develops in the body after surgery. When small blood vessels are disrupted, blood plasma can seep out into the surgical area. Further, the inflammatory process can lead to additional fluid exudate. Seromas are different from hematoma (collections of blood), and from abscesses (collections of pus). Seromas can also sometimes be caused by injury, such as when the initial swelling from a blow or fall does not fully subside. The remaining fluid causes a seroma that the body usually gradually absorbs over time (often taking many days or weeks); however, a knot of calcified tissue sometimes remains." 
So I guess we will know more in two weeks.  
