In the fourth season opener, Bonnie and Adam's relationship is tested when he moves in with her and Christy for a few weeks. Also, Christy learns the hard way that it may be a mistake to try and meet men with Jill.

Bonnie fears she's become undesirable when she catches Adam smoking pot before sex, and Christy tries to smooth things over between them.

Christy and Bonnie worry that Roscoe has a drug problem when Baxter and Candace catch him smoking pot.

Christy and Bonnie rush to a sick Violet’s side, only to find out that having mono is the least of her worries.

Christy becomes overprotective and keeps a constant eye on 12-year-old son Roscoe after discovering he's been using drugs and alcohol.

Christy and Bonnie worry about Jill after her cry for help on the anniversary of her mother's suicide.

Christy and Bonnie dip back into illegal activities, and Adam questions their morality.

Christy and Bonnie have their hands full when Adam’s hard-partying friends come for a visit.

Christy feels left out when Bonnie and the ladies keep Jill’s pregnancy a secret.

Bonnie encourages Christy to pursue Marjorie's charming nephew, Nick, despite the fact that he's been declared off limits.

Christy, Bonnie, Jill and Wendy accidentally eat pot-filled cookies.

Christy is worried Bonnie is jeopardizing her relationship with Adam when Bonnie connects with a handsome stranger.

A heartbroken Bonnie drives everyone crazy, so Christy begs Adam to take Bonnie back.

When Bonnie discovers Adam is still close with his ex-wife, Danielle, Christy worries the emotional fallout could jeopardize Bonnie’s sobriety.

When Christy and Adam get into a car accident, Bonnie is hurt to discover she is neither of their emergency contacts.

Christy helps Jill adjust to being a new foster mother, and Bonnie has trouble convincing tenants that she’s a good building manager.

Following the death of Bonnie’s mother, Christy and Bonnie learn that she kept a very big secret.

Christy annoys everyone when she adopts her new boyfriend Brad’s healthy lifestyle, and Bonnie and Adam decide to take the next step in their relationship.

When Marjorie takes a break from the group, Bonnie becomes the go-to for everyone's problems and Christy tries to overcome a painful memory from her past.

Christy and Jill take Emily to see her biological mother, Natasha, in rehab where they make a surprising discovery, and Bonnie watches Adam’s dog while he’s out of town.

In the season finale, Christy tries to help when Bonnie gets into trouble with the IRS but, realizing she’s in over her head, she encourages Bonnie to seek help from her newfound brother, Ray.