Webthis gender bias significantly affects not just sibling relationships, but the relationship with the entire family. Birth order and age spacing also play a key role in. Webrivalry and competition towards one another’s siblings often lead to physical and verbal altercations.

Webkaren's mother is changing the love/hate balance between karen and her brother. She is destroying the relationship between the two of them by favoring him. Webthe prevention of sibling jealousy was in the scientific air. Historian peter stearns puts the rise in sibling rivalry in 1920s america down to a number of significant.