NEW YORK (AP) -- Some experts in sibling research say the powerful bonds that can develop between brothers may have played a role in the actions of the suspects in the Boston Marathon bombings.
Tamerlan Tsarnaev, 26, who died last week in a shootout with police, and his 19-year-old sibling Dzhokhar, are hardly the first brothers involved in criminal acts. Three pairs of brothers were among the 9/11 terrorists and three brothers were convicted in 2008 for planning to attack soldiers at Fort Dix in New Jersey.
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Tamerlan seemed to be the dominant sibling in the family, and relatives say he was a role model for his younger brother and sisters.
Northeastern University criminologist James Alan Fox says in many criminal enterprises where brothers are involved, the leader is "almost always the older brother."
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