What do you think of this?

My son's g/f''s name is Sam (and she hates being called Samantha or Sammy) but I also have a dog named Sam (which I've called him for years) and to make it worse I also have a pet gerbil named Sam, which I call Sam #2 so I am calling her Sam #3? She seems to be insulted and thinks that her name should be elevated to a higher status to simply Sam and the dog should be called Sam #2 and the gerbil Sam #3 but he is used of being called Sam#2. Am I being mean or insensitive to her needs and what should I do about it?