Research Paper The International Journal of Indian Psychology ISSN 2348-5396 (e) | ISSN: 2349-3429 (p) Volume 6, Issue 2, DIP: 18.01.026/20180602 DOI: 10.25215/0602.026 http://www.ijip.in | April - June, 2018 2018 © Rathnasabapathy M, Wesley J R, Maharishi R & Athilakshmi R; licensee IJIP. This is an Open Access Research distributed under the terms of the Creative Commons Attribution License (www.creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any Medium, provided the original work is properly cited. Understanding Sibling Influences: The Effects of Number of Siblings and Order of Birth on Psycho-Social Behaviour among Adolescents Girls Maya Rathnasabapathy 1 *, J. Reeves Wesley 2 , Maharishi R 3 , Athilakshmi R 4 ABSTRACT This study attempts to examine the impact of number of siblings and order of birth on Psycho-social behaviour among Adolescents girls. The group consisted of 1218 adolescents girls in the age group of 13-18 years selected by convenient sampling method. Twelve Government schools were selected from twelve districts of Tamil Nadu. The results found that there is a significant difference between number of siblings and order of birth across the psychological and social factors such as emotional intelligence, resilience, stress, family environment, school problem, social problem and personal problems. Keywords: Number of siblings, order of birth, Psychological, Social, adolescent’s girls British Household Parrel Survey explored the effect on child’s educational attainment based on family size and birth order. The result indicated that the children share in family’s educational resources decrease with birth order and also children from larger family had lower levels of education. Research on sibling interrelationship explain the social dynamics between them and its impact on youth development. Downey and Conden (2004) in their study found children showed poor social skills in kindergarten who had no siblings Ozabaci (2006) in his study on effects of family size and number of siblings on Emotional Intelligence found that family environment affects development of the ego conflict of the child and his social and emotional development. Sibling relationships are special since they 1 Psychology, School of Social Sciences and Languages, Vellore Institute of Technology, Chennai – 600127, Tamil Nadu, India 2 VIT Business School (VITBS), Vellore Institute of Technology, Chennai – 600127, Tamil Nadu, India 3 Psychology, School of Social Sciences and Languages, Vellore Institute of Technology, Chennai – 600127, Tamil Nadu, India 4 Psychology, School of Social Sciences and Languages, Vellore Institute of Technology, Chennai – 600127, Tamil Nadu, India *Responding Author Received: April 1, 2018; Revision Received: April 15, 2018; Accepted: May 29, 2018