It is rude to be nasty to elderly people.
Doug's elderly mom needs help going to the doctor once a month.
Doug wants to save his vacation time at work.
Doug decides to hire a caretaker who can take his mom to her appointments and help with other things around the house.
"Doug tells his mom he's tired of driving the ""old bat"" around and tells her to find someone else to take her."
Doug's mom feels cared for and enjoys the companionship of the caretaker.
Doug's mom is hurt and feels let down by her son.