It looks as if my studio has become a twin-mecca!  I was recently photographing a local fertility specialist for a commercial assignment and I had to tell the Doc about my recent 'wave of twins'- and to thank him!   I was told that it is the goal of the practice to NOT produce twins. 
I hope I didn't offend the gifted & talented Doctor- but I felt I have to thank somebody (in addition to the parents, of course) so... Dear God: thank you for all the two-fers!