Does the regret and remorse in case 1 actually matter? Enormously. For once, it could plausibly drive most people who did that to suicide.

If it does, what do you want to say about parents who would feel more regret or remorse given the death of their child than given his or her continued life?

Is there a miscommunication here? parents who would feel more regret or remorse given the death of their child than given his or her continued life - that sounds to be, like, most parents in general, and ALL the parents whom society approves of.