I'm sorry for whomever you have in mind, but I absolutely reject the mentality that non-bullying humour must be curbed in case someone might have their feelings hurt - especially the kind of hurt where people take offense where none was intended.
People are grieving and gently pointing out that perhaps other analogies might be better. There's no ranting nor pitchforks. Just a polite gentle reminder that the loss of a child is an incredibly traumatic thing.
That's a reasonable point. The analogy isn't so amazing that it is crucial to understanding. It cod easily be tweaked.
I would have used it unmodified, but now i will try to change it to avoid dead children.