After months of rumors, Nicole Richie confirmed Tuesday that she is pregnant. "Yes I am. We are," Richie told ABC News' Diane Sawyer for an interview to be aired this week. "I'm almost four months." Richie's boyfriend, Good Charlotte frontman Joel Madden, is the father, she told ABC, which issued a news release about the interview.

The 25-year-old star of "The Simple Life" and on-again pal of Paris Hilton also talked with Sawyer about her guilty plea last week to driving under the influence and the resulting four-day jail sentence.

"I have a responsibility and it's something that I did wrong, and if I could personally apologize to every single person that has lost a loved one from drunk driving, I would," Richie said. "And unfortunately I can't, but this is my way of paying my dues and taking responsibility and being an adult."

Richie also shared her thoughts on her hard-partying contemporaries and what effect their bad behavior has on young fans.

The interview will air on "Good Morning America" on Thursday and Friday and on "20/20" Friday night.