Stress and depression among parents can affect babies as young as nine months and harm their development, a new report has claimed.
Research on infant development found mothers and fathers with high levels of stress show less sensitivity to their children.
Minister for Children Frances Fitzgerald said the findings, which are part of the Government-funded Growing Up in Ireland study, demonstrate how family influences can impact children from such a young age.
"This research highlights the important role of parenting and family contexts for children's developmental outcomes, and the impact of factors such as gestational age, birth weight and parental sensitivity or parents' ability to interact effectively with their infants," Ms Fitzgerald said.
"The new Child and Family Agency to be established in 2014 will bring together key agencies to ensure children and families get the services they require in a timely and effective manner."
The report, published by Elizabeth Nixon, Lorraine Swords and Aisling Murray, found that stress among mothers was strongly associated with a difficult temperament from an infant.
It suggested that difficult youngsters tend to demand more tolerance and patience from parents and can therefore be more stressful to deal with.
But it added that parents who are stressed may perceive their children to be more difficult to deal with.
The study, entitled Parenting and Infant Development, examined nine-month-old babies and how their development was associated with the parenting they received.
It found that mums and dads who were more sensitive in their interactions had babies with higher development scores - however the extent of that association was relatively small.
Report co-author Dr Nixon, from Trinity College Dublin, said: "These findings show that even from a very young age, the sensitivity that parents show when interacting with their babies is important for their development.
"The findings also show that parenting does not happen in a vacuum. Both mothers' and fathers' parenting behaviours can be negatively affected by stress and depression but babies can be protected from these potentially negative influences if sensitive parent-child interactions can be maintained."
She also noted children born prematurely or with a low birth weight may be at risk of poorer developmental outcomes.
But she added that it may be possible that they just need time to catch up.
The study was based on the first wave of in-depth interviews with the parents of over 11,000 nine-month-old children.
The youngsters and their families were subsequently interviewed at three years of age and have just been interviewed at five years of age to assess how much their lives have changed since.