"Yesterday we bought her a doll."
Translation:Ayer le compramos una muñeca.
@Julie: Without using technical grammar language (My eyes glaze over when I hear words like “indirect object”) I think of ‘le’ as meaning ‘to him/her’. Even though we don’t include the word ’to’ in English, it is implicit in the meaning. The direction is going toward her. The same in Spanish, the’ a’ is not necessary. There is this shorter way of saying the same thing.