Are parents allowed to hide a diagnosis of cancer from a sick child ?

Notification: Parents are generally "allowed" to do whatever they feel is in the best interest of their child. This only changes when they do something that is overtly harmful to their child. Assuming the cancer is treatable (as many childhood cancers are), i'm not sure why a parent wouldn't tell the child about their illness. That would certainly make it easier to understand why they're undergoing treatment.

Why would you?: Kids deserve to know what's happening to them and are amazingly resilient. It may be difficult to hide the truth with all the treatment & tests they will need. Outcomes may be better if they are involved in their care.

They will find out: Children are very observant. They will find out, and if that happens by someone other than their parents and doctors, they will feel a combination of confused, hurt, betrayed, and they will be even more scared than if they were told upfront. It is not an easy thing to do, but it is the right one. Your pediatric oncologist is there to help. Legally speaking, i don't know. I have never hid this.