The right answer is: an elderly person.
Food poisoning makes people sick at any age, but among seniors, whose immune systems are more vulnerable and weaker, the consequences can be dramatic. That's why caring for an elderly person at home is a good way to make sure they eat healthy and safe.
Closer to a dog though has some cat qualitys XD<span />
The purpose of the kidneys is to filter waste from the blood, and other things like water, glucose, amino acids, some minerals/vitamins, and other small molecules can also get filtered out. Reabsorbtion of water in the kidneys allows the body to maintain a fluid balance (drink a lot and you pee more cause you have an excess of water). As for the other aforementioned things, they're often needed for metabolic processes (such as certain enzyme functions) so loosing it to waste decreases efficiency and efficacy of other bodily processes.
A medical oncologist treats cancer using chemotherapy or other medications, such as targeted therapy or immunotherapy. A surgical oncologist removes the tumor and nearby tissue during surgery. A radiation oncologist treats cancer using radiation therapy.