Children between the ages of 10 and 14 could be protected from depression if they have a sister. Researchers from Brigham Young University in Utah studied 395 families with more than one child, at least one of whom was an adolescent between the ages of 10 and 14. The researchers gathered a range of information about the families and followed them up again one year later. Having a sister was found to protect the adolescents from feeling lonely, unloved, guilty, self-conscious and fearful regardless of whether the sister was younger or older or how far apart they were in age. Having a loving brother or sister promoted good deeds such as helping a neighbour or looking after other children at school and in fact the relationship between sibling affection and good deeds was twice as strong as that between parenting and good deeds.
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