SPOILER!
>Olson and McElhenney are expecting a son in about a month or so; Olson said that they hid the pregnancy while shooting the first block of episodes, but couldn't hide it in the second set. Hence the episode "Who Got Dee Pregnant?" episode that was shown to the critics. In it, Dee tells the gang that one of them got her pregnant at a Halloween party, generating an episode's worth of hazy, 'Rashomon'-style rememberances that involve the Waitress, the McPoyles, and Artemis.
>When she couldn't come up with an eloquent response for an audience question about the inspiration behind Sweet Dee, she took a cue from the crowd's shouts and answered "Boner. My answer is boner."