During the bladder stimulation technique, parental perception of pain will be assessed using the Numeric Rating Scale (NRS). The research assistant will administer the NRS to the parent immediately prior to the procedure (T0), during the bladder stimulation technique (T1), 1 minute after completion of the bladder stimulation technique (T2) and 5 minutes after completion of the bladder stimulation technique (T3). For infants undergoing catheterization, parental perception of pain will also be assessed using the NRS at similar time intervals.