A study of 80 pairs of middle-income Canadian mothers and their year-old babies has revealed that children of mothers who answered their children's requests for help quickly and accurately; talked about their children's preferences, thoughts, and memories during play; and encouraged successful strategies to help solve difficult problems, performed better at a year and a half and 2 years on tasks that call for executive skills, compared to children whose mothers didn't use these techniques.
(2010). From External Regulation to Self-Regulation: Early Parenting Precursors of Young Children's Executive Functioning.
Child Development. 81(1), 326 - 339.