Every member of ambulance staff I have ever spoken to (for myself or for a person I was responsible for) has tended to include in their "okay, we don't need to take you to hospital" speech, advice to make a follow-up appointment with a GP, and instructions to keep an eye on things and call them again if any additional symptoms crop up before the GP has been consulted. I always figured this was pretty much a standard caveat? That said, I can't begin to imagine what that father is going through - his little boy dies, then he and his wife are arrested for murdering the kid, that's more than any person can be reasonably expected to cope with and remain completely calm. No wonder he wants to sue someone. I suspect the paramedics are just the most viable target.