Firstborn children often have slightly higher IQs and complete more years of schooling than their younger siblings, but birth order accounts for no meaningful differences in personality.

Middle children occupy a special place in the sibling line-up, between the eldest and the youngest. Now a study reveals that they develop particular traits because of this.

Sibling relationships are important. While friendships come and go, you’re stuck with your siblings. This relationship is oftentimes one of the longest relationships in a person’s life.

The study used the HEXACO Personality Inventory to assess 6 personality traits based on sibling birth order: honesty-humility, emotionality, extraversion, agreeableness, conscientiousness, and ...

New research from BYU highlights how subtle parental preferences—based on birth order, personality, and gender—can shape sibling relationships and family dynamics. Siblings share a unique bond ...

Equal parts birth-order stereotyping and pop psychology, the term describes a heady cocktail of perfectionism, self-sacrifice, guilt, and sibling resentment thanks to the double whammy of being ...