CinemaBlend Fans were stunned when Mom star Anna Faris, who'd been with the series for its entire seven season run, announced that she'd be leaving prior to Season 8 going into production. The move also, reportedly, shocked everyone who works on Mom, and now remaining lead Allison Janney has opened up about what it's been like to film the hit sitcom without Faris. While everyone at Mom was said to have been thrown into a bit of a tizzy when Anna Faris chose to leave so that she could pursue other projects, they did decide that the show must go on, and have been diligently working on Season 8 without her Christy around. But, that doesn't mean that it's been completely easy, and when asked recently by Ellen DeGeneres on her daytime show what it's been like filming without her former partner in addiction recovery antics, Allison Janney said: