Contact Photos iPhone

New to the iphone but loving it.  I am not very tech savvy so for me this is kind of a complicated question about assigning photos to contacts.  As an example of my issue:  Several couples in my contacts share the same home phone but each has his/her own cell and work number.  I have listed each person separately in my contacts.  In these cases, both spouse's listings haves the same home tel. number but they obviously have different cell and work numbers.  I would like to attach a photo of the couple for the home numbers and photos of the individuals for their separate cell and work numbers.  Is this possible without creating separate contacts for their cells and work telephones?  Or how about this:  if I put Mary's photo on her listing, I assume it covers all three of her phones-home, cell, work.  What happens if I assign John's photo to his listing  which includes the home telephone shared with Mary?  What will show up when one of them calls me?  Will the phone explode or will Siri's mind blow?   Am I missing something?  Thanks for any help.