Why do we have children when we know we will be forcing them to face their own mortality?

Why do we decide to have children when we know (subconsciously or otherwise) that we will be inevitably forcing a nascent sentient organism with the inevitable question of its own death? What kind of existence do we live in now that we should allow a cirstance such as our own inevitable demise to be presented in such an absolute manner to something that we had a role in creating?