title: Trajectories of antisocial behaviour towards siblings predict antisocial behaviour towards peers.
abstract: BACKGROUND
  Young siblings' antisocial behaviour is common yet its impact has received relatively little research attention.
  
  
  METHODS
  We examined trajectories of antisocial behaviour for a socially diverse sample (n = 99, 58 boys and 41 girls) who were filmed with their older siblings (52 boys and 47 girls) at ages 3 and 6 and with unfamiliar peers at age 6. Latent growth models were used to analyse three indicators of antisocial behaviour (refusal to share/interact, bullying and harming).
  
  
  RESULTS
  The average trajectory of antisocial behaviour towards siblings was stable and particularly high for boys with brothers and for children of mothers with no educational qualifications. Sustained and escalating antisocial behaviours towards siblings predicted bullying and refusals to share/interact with unfamiliar peers, independent of associations with concurrent antisocial behaviour towards sibling.
  
  
  CONCLUSIONS
  These findings highlight the importance of a developmental perspective when examining antisocial behaviour between young siblings.
authors.affiliation: Centre for Family Research, University of Cambridge, Free School Lane, Cambridge, UK. rad35@cam.ac.uk
authors.forename: Rosie
authors.initials: R
authors.lastname: Ensor
authors.forename: Alex
authors.initials: A
authors.lastname: Marks
authors.forename: Lorna
authors.initials: L
authors.lastname: Jacobs
authors.forename: Claire
authors.initials: C
authors.lastname: Hughes
mesh_terms: D000374:Aggression; D000987:Antisocial Personality Disorder / Q000453:epidemiology* / Q000523:psychology*; D058445:Bullying; D002648:Child; D002652:Child Behavior / Q000523:psychology*; D002675:Child, Preschool; D004522:Educational Status; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D009035:Mothers; D009483:Neuropsychological Tests; D010379:Peer Group; D010552:Personality Assessment; D010553:Personality Development; D010988:Play and Playthings / Q000523:psychology; D012307:Risk Factors; D012737:Sex Factors; D035781:Siblings / Q000523:psychology*; D012919:Social Behavior