There are reported cases of relational aggression among learners at public pre-schools in Kenya, however, very scanty research has been done in this regard. The study examined parent attachment relationships and aggressive tendencies among learners during early years in Kenya. Ex-post facto research design was adopted. The sample size consisted of 348 pre-school learners and 277 parents obtained by using the simple random sampling technique. The Parent-child Attachment and Aggressive Tendencies Questionnaires were used to collect data from parents. Construct validity was ensured by the researchers in psychology and early childhood education. Cronbach’s alpha was used to establish the reliability of the questionnaires and the subscales had alpha of between 0.7 to 0.9. The results indicated a strong negative correlation (n=68; r = -.827; p < 0.05) between secure attachment and aggressive tendencies; weak (n=80; r =.248; p=.026), positive correlation between parent-child ambivalent attachment and aggressive tendencies; a fairly strong positive correlation (n=40; r =.684; p < 0.05) between parent-child disorganized attachment and aggressive tendencies and a weak positive correlation [n=48; r =.043; p =.772 between avoidant attachment and aggressive tendencies. The study recommends that teacher counselors should ensure early screening for those with vulnerable attachments.