Most people do not doubt that pets are great companions and that they are good for everybody (young and old people). To many adults, especially those who live alone, animals are like family members. They fulfil your need for affection and attention like only animals can do. To children, in addition to being their companions all day, animals also serve to help them learn day-to-day things. Animals show the circle of life in an accelerated way compared to human beings (birth, youth, adulthood, old age and dying). They also show children other things related to life such as having an accident, getting ill and knowing how to take care of themselves. As these phases are more accelerated in animals than in human beings the children learn about them through the animals. Moreover, animals help the children to develop their sense of responsibility, since they need to be taken care of constantly. In a study performed by Robert Bierer it was concluded that children, aged ten to twelve who had animals had more empathy towards others and higher self-esteem. Pets also help children to reduce their anxiety, tediousness and fear and to develop a better capacity to integrate and to be more focused in school.
source:
http://www.bianca.pt/english/index.php?option=com_content&view=article&id=18&Itemid=80