1. A method for identifying a photo using a data structure, wherein the data structure is a family tree representing genealogical information, and wherein there are multiple facial images in the photo, the method comprising: displaying a photo at a user interface; displaying at the user interface a data structure having a plurality of data nodes, each data node representing one or more data records associated with a person; determining whether there is a relationship between the displayed photo and one or more of the data nodes; identifying at the displayed data structure any data node that has a relationship to the displayed photo, by selecting one of the data nodes at which there is a match of characteristics of the person associated with that node to a person represented by a facial image in the displayed photo; presenting the selected one data node in the family tree to a user at the user interface; estimating the age of the person corresponding to each facial image in order to determine the number of generations represented by the photo; selecting nodes corresponding to those generations in the family tree; and presenting the nodes corresponding to those generations in addition to the selected one node.