Poor Bonnie fell victim to the Parvovirus (aka Parvo) on 6 September 2021. She was found by Christine abandoned in Bacong cemetery on 19 August 2021. She was perhaps 6 weeks old. Parvo is not airborne and doesn't cause much of a problem to older vaccinated dogs but it is really dangerous to young puppies.
It affects the digestive system and some of the first signs are loss of appetite, vomiting and poop in the blood. It can kill very quickly - often 3 days after the first signs. There is no cure as it is a virus, all you can do is support the immune system and keep the puppy hydrated.