"There's something about early friendships -- when they work well, they help children learn how to behave constructively in relationships," said Kramer, co-editor with Lew Bank on a special issue of the journal, "Sibling Relationship Contributions to Individual and Family Well-being."
"When early friendships are successful, young children get the chance to master sophisticated social and emotional skills, even more than they do with a parent. When parents relate to a child, they do a lot of the work, figuring out how what the child needs and then accommodating those needs. With another child, that doesn't usually happen," said Kramer, a U. of I. professor of applied family studies.
The research showed the benefits of early friends are long-lasting. Children who had a positive relationship with a best friend before the birth of a sibling ultimately had a good relationship with their sibling that lasted throughout adolescence, Kramer said.
And children who as preschoolers were able to coordinate play with a friend, manage conflicts, and keep an interaction positive in tone were most likely as teenagers to avoid the negative sibling interaction that can sometimes launch children on a path of antisocial behaviors, she added.
Early friendships also predicted future competence in other sorts of relationships and in certain forms of personal well-being -- for example, fewer behavior problems or less depression or anxiety later in life, Kramer said.
"Even in early childhood, close friendships have been shown to provide unique benefits for children encountering stress," she said.
The 13-year study followed 28 pairs of siblings, beginning when the oldest child was between three and five years old and the parents were expecting the second child. Researchers assessed the quality of the firstborn's relationship with his mother during the last trimester of the mother's pregnancy as well as the quality of the child's relationship with a best friend.
And, although the mother-child bond was important for the future sibling relationship, the child's relationship with a best friend was a stronger predictor of future sibling harmony, she said.
After the younger child was born, researchers visited the family frequently and videotaped the siblings, coding them for conflictual, competitive, cooperative, and prosocial behaviors, with the last observation occurring when the elder siblings were 17 years old and the younger siblings were 13.
There was a very strong link between children who had positive interactions with a friend before the sibling's birth and a later positive relationship with the sibling, Kramer said. "This study shows that it's very important to help children develop good friends, particularly in the preschool years."
"From birth, parents can nurture and help develop these social competencies by making eye contact with their babies, offering toys and playing with them, and encouraging them to interact with other children as soon as they are developmentally able to do so," she said.
Preschools, child-care centers and providers, and schools should also learn more about children's socioemotional development so they can provide educational experiences that will help children learn to get along with each other better, she said.
"The trickiest part is helping kids manage some of the negative emotions they experience," Kramer said. "Children can learn a lot about handling frustration as a part of the sibling relationship. Brothers and sisters can be awfully frustrating."
And firstborn children who have had a good friend are a step ahead of the game, Kramer said. "For children, just knowing that someone likes them is validating. That confidence, and the experience they've gained from participating in a friendship, can really pay off later in life in terms of beneficial relationships with brothers and sisters, friends, and other personal relationships."
The study was co-authored by Amanda Kowal of the University of Missouri-Columbia.
It was funded by the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture.
EDITOR'S NOTE: Researcher Laurie Kramer can be reached at 217-333-0628 or firstname.lastname@example.org.