Which IM program is she using? If it is Windows Live Messenger then open a chat window, go to tools, emotions. You can remove them all in here.
Most of the default ones are set to key combinations that you would rarely use in a message otherwise such as :) :@ etc. My guess is that her or someone else (children?) have set their own custom emotions to frequent key combinations.
Some people I talk to have loads of them and it is really annoying trying to figure out what they are saying. If you right click the emotion, there will be a button that says 'add'. If you click this, it tells you what key combination they have typed to get it but make sure you don't add it to your own system. It just helps you to figure out what they are trying to say.