The incidence of HL increases with age and is rare in children under age 5 years, according to the ACS. A 2021 publication notes that it’s the most common lymphoma in individuals ages 10–19 years and the most common cancer in adolescents ages 15–19 years.
The ACS also says NHL is more common in younger children than HL but is still rare in children under 3 years. The exact incidence of NHL can vary by type.