My s/o and I were talking the other night and the topic of twins came up.
If identical twin women married & had children with identical twin men, would the children each pair produced look the same??
I know this likely sounds like a totally idiotic question, but everyone I ask has no idea!
             
            
              
              
              
            
            
           
          
            
            
              Nope. Remember, each twin has TWO copies of everything; there is still a selection process going on.
However, it is more likely that their kids will look very similar than for randomly-selected couples.
             
            
              
              
              
            
            
           
          
            
            
              Since their parents have effectivly the same genetic material, the cousins would be just like siblings.   While brothers & sisters can look similar, it would be as unlikely for the cousins to look exactly the same as it would be for siblings to look exactly the same.