The investigators propose a prospective study where pediatric patients who are undergoing elective umbilical hernia repair will be randomized pre-operatively to receive either pre-incisional, ultrasound guided percutaneous rectus sheath block or intra-operative rectus sheath block under direct visualization prior to closure of the skin. The primary outcome is the post-operative pain rating based on the Wong-Baker Faces Pain Rating Scale (WBFPRS) following umbilical hernia repair. Additional outcomes measured will include: operative times, the use of intravenous/oral opioid and/or non-opioid medication in the post-operative period, duration of analgesia following surgery based on time to first rescue analgesic, intra-operative hemodynamic changes, post-operative hemodynamic changes, incidence of side-effects, and complications. Patients/patient guardians will receive a sheet to document post-operative WBFPRS scores, oral opioid and non-opioid medication administration once discharged to home for a total of 5 days.