Little old lady and 3 sons

Three sons left home, went out on their own and prospered. Getting back together, they discussed the gifts they were able to give their elderly Mother.
The first said, “I built a big house for our Mother.”
The second said, “I sent her a Mercedes with a driver.”
The third smiled and said, “I have got you both beat. You remember how Mom enjoyed reading the Bible? And you know she can’t see very well any more. I sent her a remarkable parrot that recites the entire Bible. It took Elders in the church 12 years to teach him. He’s one of a kind. Mama just has to name the chapter and verse, and the parrot recites it.”
Soon thereafter, Mom sent out her letters of thanks:
“Milton,” she wrote one son, “the house you built is so huge. I live in only one room, but I have to clean the whole house.”
“Gerald,” she wrote to another, “I am too old to travel any more. My eyesight isn’t what it used to be. I stay most of the time at home, so I rarely use the Mercedes. And the driver is so rude!”
“Dearest Donald,” she wrote to her third son, “you have the good sense to know what your Mother likes. The chicken was delicious!”