Communicating with babies in infant-directed-speech is considered an essential prerequisite for successful language development of the little ones. Researchers have now investigated how the mood of mothers in the postpartum period affects their child's development. They found that even children whose mothers suffer from mild depressive mood that do not yet require medical treatment show early signs of delayed language development. The reason for this could be the way the women talk to the newborns. The findings could help prevent potential deficits early on.