- There are 3 groups of participants being recruited: 1) those who have a child who has been diagnosed with cancer at least 3 months prior to enrolling on this study and are currently undergoing cancer treatment, 2) those who have completed treatment at age 21 or younger (without evidence of disease) within the previous 3 years, and 3) those who have a child who has been diagnosed with NF1 at least 3 months prior to enrolling on this study.