See Section 7.0 of the Larimer County Land Use Code regarding Special Events. 

A Personal Event is defined as the following, and is not subject to Section 7.0 standards. 

Personal Event. A gathering for social activities such as family celebrations (including but not limited to wakes, funerals, anniversaries, graduations, and weddings), parties (including but not limited to dinner parties, barbecues, house warming parties) and/or gatherings (including but not limited to demonstration parties, study groups, club meetings) of family members and friends of the owner/resident of the property. Personal events must be hosted by an individual that resides on the property. A personal event shall be accessory and incidental to use of the property as a residence.