When my youngest was 4, he would actually talk about "when Sallie and me get married." Sallie also referred to him as her boyfriend. The two of them had known each other since birth and spent a lot of time with each other at preschool, church activities and big school things (older siblings at same school). But alas, before the preschool year was over, she decided that she wanted an older man -- one of her 10-year-old brother's friends.