Honestly, I don't really see a problem and it's natural for kids to like all animals---especially mammals because they're the most like us. I mean, it's not like your girl is likely to grow up to be a pig farmer if you let her think that pigs are cute. Love of animals is a really nice way for kids to develop the qualities of mercy and compassion because they are often among the few beings that are weaker/more powerless than them... I don't believe that Islam teaches that certain animals are "bad"--the Prophet's companions hunted with dogs---just that certain animals are unclean for different purposes.
Obviously it is important for her to understand that as Muslims we don't eat pork, and that cleaning ourselves after contact with a dog/pig/unclean things is part of making wudu. She's getting to an age where she should be learning to pray, so you could just reinforce these ideas each time you practice wudu with her----"we do this before we pray, and we should also do it if we touch a dog or pig, etc., etc." She's also getting to an age where she will probably begin to have more exposure to non-Muslim kids her age, so making sure she begins to develop an awareness of what foods she can and can't eat and helping her to recognize risky situations is important...