Sisters spread happiness while brothers breed distress, experts believe. 专家相信，姐妹为家庭播洒快乐，而兄弟让家庭陷入忧愁。

　　Researchers quizzed 571 people aged 17 to 25 about their lives and found those who grew up with sisters were more likely to be happy and balanced. 研究人员在对571名年龄在17至25岁的青年人进行调查后发现，那些在成长过程中有姐妹相伴的人长大后更快乐、心理也更平衡。

　　The University of Ulster said having daughters made a family more open and willing to discuss feelings. 阿尔斯特大学的研究人员说，家中有女儿有助于家庭成员之间敞开心扉、增进交流。

　　They said the influence of girls was particularly important after distressing family events such as marital break-ups. 女孩对家庭有着巨大的影响力，这种影响力在家庭遭遇诸如夫妻离异这样的重大变故后，会尤为明显地体现出来。

　　The findings are due to be presented at the British Psychological Society in Brighton on Thursday. 该项研究成果将于周四在英国心理学会在布莱顿召开的会议上公布。

　　During the study, participants filled in psychological questionnaires which researchers used to assess a range of issues, including whether they had a positive outlook and any mental health problems. 在研究过程中，研究人员通过问卷调查的方式，对受访者是否心态乐观、是否患有精神抑郁疾病作了深入的了解。

　　Lead researcher Professor Tony Cassidy said: "Sisters appear to encourage more open communication and cohesion in families. " 该项研究的负责人托尼•卡西迪教授说：“家里有姐妹更有助于家庭成员加强交流并增进凝聚力。”

　　"However, brothers seemed to have the alternative effect. " “相反，兄弟们似乎只能增加家人间的隔膜。”

　　"Emotional expression is fundamental to good psychological health and having sisters promotes this in families." “情感的表达对于个人心理健康有着重大作用，家有姐妹能够进一步强化这种家庭纽带。”

　　He said many of the participants had been brought up in families where parents had split and the impact of sisters was even more marked in these circumstances. 他说，很多参加调查的人都来自单亲家庭，姐妹关系对这些人起到了非常显著的积极影响。