The rat poison is making it's way down the food chain.....ie - the rat eats it, a cat or dog eats the rat, then the pet dies.
(the pet; dies; T:then) Context(the pet dies,List([112, 124))):(a cat or dog; eats; the rat)
the pet dies,List([112, 124))
the pet a cat or dog
dies eats
T:then
the rat