|Played by|| Mark Lenard|
David Considine (as a teenager)
|Debut||306: Journey in the Spring|
As a teenager, he would sometimes have quarrels with his younger brother Charles but he would help Charles if he was in trouble. He tried to help Charles with his shyness toward girls but when he failed to measure up he teased him and the two fought as usual. (Episode 416: I Remember, I Remember) His mother described him as more like her in terms of settling down in one place and staying put. Later as he became an adult, he married Eliza Ann Caroline's sister and had two children. He lived in a house on a modest piece of land in Wisconsin with his wife and two children Amelia Ingalls and James Ingalls.
It seemed that Peter was an ornery and self-interested man always thinking of his own personal family first unlike Charles who would at times risk himself for a strangers or for a neighbors' sake. He chose not to see his father after his Ma died because he didn't want his despair and self-pity affecting him or his family and to remember him as he was when he was a child, unlike Charles who wanted to save him from himself. When Charles came to visit, he became angry with his brother's warmer feelings toward his father as an implication that he hadn't any respect for his father and wasn't treating him right. (Episode 306: Journey in the Spring (Part 1)