Given the following context:

Brink has recently taken Pud's (Bobs Watson) parents in an auto wreck.  Brink later comes for Gramps. Believing Brink to be an ordinary stranger, the crotchety old Gramps orders Mr. Brink off the property. Pud comes out of the house and asks who the stranger was. Gramps is surprised and relieved that someone else could see the stranger; he was not merely a dream or apparition.
Pud tells Gramps that when he does a good deed, he will be able to make a wish. Because his apples are constantly being stolen, Gramps wishes that anyone who climbs up his apple tree will have to stay there until he permits them to climb down. Pud inadvertently tests the wish when he has trouble coming down from the tree himself, becoming free only when Gramps says he can.
Pud's busybody Aunt Demetria has designs on Pud and the money left him by his parents. Gramps spends much time fending off her efforts to adopt the boy.
Brink takes Granny Nellie in a peaceful death just after she finishes a bit of knitting. When Mr. Brink returns again for Gramps, the old man finally realizes who his visitor is. Determined not to leave Pud to Demetria, Gramps tricks Mr. Brink into climbing the apple tree. While stuck in the tree, he cannot take Gramps or anyone else. The only way anyone or anything can die is if Gramps touches Mr. Brink or the apple tree.
Demetria plots to have Gramps committed to a psychiatric hospital when he claims that Death is trapped in his apple tree. Gramps proves his story first by proving that his doctor, Dr. Evans, can not even kill a fly they have captured. He offers further proof of his power by shooting Mr. Grimes, the orderly who has come to take him to the asylum; Grimes lives when he should have died.

answer the following question:

Who tells the crotchety old man about the wish that ends up catching Death? 

Pud