Children aged 2;11 to 8;3 sang informally, once in the presence of the
ir infant sibling and once when the infant was out of view. Paired exc
erpts from 22 children were presented to adult listeners, who were req
uired to identify the infant-directed excerpt in each pair. Listeners'
accuracy was above chance levels but below what would be expected for
mothers' singing in comparable contexts. Children altered their singi
ng style in the infant's presence by singing at a higher pitch level a
nd with a different vocal quality.