The following paper aims to investigate how student teachers relate to the suitability of their student teacher peers after experiencing challenges to their emerging teacher identity, resulting in emotional responses. A constructivist grounded theory study was conducted in which 18 student teachers participated. Data from 14 individual interviews and one focus group were analysed. Findings revealed that encounters between student teachers sometimes resulted in emotional responses. When the student teachers were emotionally challenged by their peers, their emerging teacher identity was challenged. In addition, the student teachers compared themselves with those peers whom they judged as unsuitable and constructed a self-image of being suitable. This comparative process was connected to three suitability norms: (1) being perceived as having the right values (2) being perceived as having social skills and (3) being perceived as committed to in-depth learning as a teacher.