I think that the environment is a great factor in shaping peoples' lives. My brother liked eye contacts as a baby and my mother gave him great love. My sister and I also loved him very much and played with him when he was little. He was very attached to me especially until I was in high school. After my freshmen year, I went back home and I felt the distance between us. It didn't take long for him to cling to me and wanting to hang out with me. After my sophomore year, he was definitely more independent and tended not to care so much about anything around him. He told me that he was alone for too long, that he had to adjust himself so that he won't get hurt, and won't expect anything from other people. I can feel that he has changed greatly after my absence. He avoids sharing his feelings with my parents, and my sister. Thankfully I can be on his side when he's having a hard time, he still is willing to talk to me about his personal life. He got into a car accident not long ago, and in stead of telling my father, he called me and asked for help. He complains a lot about how my parents don't trust him and how he can't share anything with them, either. He was securely attached as a child, very confident and love-giving. After 17 years he is no longer securely attached.
i agree with your views on this as i also had an elder brother. we used to play together and study together, but we separated from each other as we made our own friends in school. but he was always closer to me than my parents because i knew that my parents would get angry at somethings but my brother would understand. although we do not see each other that often now, i feel that we are still attached in a way because there are always things that we tell each other but not our parents.