Brother
(重定向自Brothers)
A brother is a male sibling.
The term brother comes from the Proto-Indo-European *bʰréh₂tēr, which becomes Latin frater, of the same meaning. Sibling warmth, or sibling affect between male siblings has been correlated to some more negative effects. In pairs of brothers higher sibling warmth is related to more risk taking behaviour although risk taking behaviour is not related to sibling warmth in any other type of sibling pair. The cause of this phenomenon in which sibling warmth is only correlated with risk taking behaviours in brother pairs still is unclear. This finding does, however, suggest that although sibling conflict is a risk factor for risk taking behaviour, sibling warmth does not serve as a protective factor. Some studies suggest that girls having an older brother delays the onset of menarche by roughly one year.