In 2000, Peter was seen having a romantic love affair with Christine King. Christine King is a sweet girl. As a loving couple, they also had a child together. However, this relationship didn't last that long as they broke up within a few years.
In 2010, Peter began dating Lauren Graham. Lauren Graham is also an actress. She is also popular as a producer and novelist.
Peter received his formal education from Gustavus Adolphus College. He graduated from there in 1987 in English literature. After that, he joined New York University's Graduate Acting Program and began pursuing his Master of Fine Arts degree. He has been active in acting since 1987. That year he appeared in the movie, Blood Harvest.
In 1990 he starred in the TV series, Carol & Company. His breakthrough role came in 2001 after he began portraying the role of Nate Fisher in the television series, Six Feet Under. In 2010 he appeared in the TV series, Parenthood and for this role, he earned a salary of $125,000 per episode. His net worth is said to be around $20 million dollars.