Children and adolescents receiving treatment for cancer experience multiple symptoms as a consequence of their disease and its treatment that interfere with the child's quality of life. Understanding of symptom assessment in children with cancer is foundational to the work of the Children's Oncology Group Nursing Discipline, whose research aims are to address knowledge gaps including understanding illness-related distress. This article is the second of a two-part summary of current evidence addressing the assessment of symptoms frequently reported by children and adolescents receiving treatment for cancer. Studies reporting assessment of pain, sadness, and symptom clusters published between January 2008 and May 2018 were included. Forty-three publications addressed pain. Pain was highly prevalent and distressing, varied in its trajectory across a cycle of chemotherapy and across multiple cycles of treatment, and correlated with biomarkers associated with the pain response. Consequences of pain were poorer functional status and emotional health. Twenty publications addressed sadness. Sadness was the most prevalent psychosocial symptom. Its prevalence decreased over the course of treatment and over a cycle of chemotherapy. Persistent sadness was of greater severity and distress. Eight publications addressed symptom clusters. These studies identified both groups of co-occurring symptoms and groups of patients with common symptom profiles. This two-article series provides evidence for the distressing nature of symptoms among children receiving cancer treatment. Efforts to support clinicians in routine symptom assessment are needed. Additional research directed at alleviating symptoms and building resilience among the child experiencing symptoms is needed.