If my 4 year old daughter was at a birthday party in at a craft store but she fell and split her lip and needed stitches are they liable?

I am sorry to hear about your daughter's injury.  Whether or not the store is liable depends upon how your daughter's fall happened.  In order for the store to be liable, you must be able to show that the store was negligent in some way.  For example, if the floor was wet or in disrepair and that is what caused your daughter to fall.  If your daughter simply fell on her own, the store is likely not going to be liable for that.  I would suggest you contact a personal injury attorney in your area and seek a consultation.  He or she will be able to hear all of the facts of your case and give you a fully informed answer as to what your legal options may be at this point.  Most personal injury attorneys offer free consultations.