第四幅图：http://images.google.cn/imgres?imgurl=http://image.cnwest.com/attachement/jpg/site1/20080608/001372d8a31409b57c2631.jpg&imgrefurl=http://www.sxtvs.com/content/2008-06/08/content_696475.htm&usg=__EqUS-CTkqfTqB2EM_NLLgIDpxEk=&h=554&w=453&sz=84&hl=zh-CN&start=56&tbnid=3WwPfPu_y4njJM:&tbnh=133&tbnw=109&prev=/images%3Fq%3D%25E8%25BE%259B%25E8%25BF%25AA%25E5%2585%258B%25E5%258A%25B3%25E9%25A6%25A5%26start%3D40%26gbv%3D2%26ndsp%3D20%26hl%3Dzh-CN%26newwindow%3D1%26sa%3DN夫妻都是棕色头发，生出金发孩子？正常吗？