The way I think the thought process has gone is......

He's a child and those responsible for his welfare are supposed to "seek medical attention" if the child requires it. The child in this case is unable to ask for anything for himself and has little knowledge about what's going on around him. That he may be terminally ill is neither here nor there and not seeking medical attention could help see him off.

If you're terminally ill, no matter whether well meaning people might see treatment as "prolonging the agony", you're not supposed to help them on their way.

If someone is terminally ill and unable to make any decisions for themselves while receiving "end of life care", you're not supposed to remove that care if it means an earlier death......... and so on.........