In this episode, Sean's ex-wife informs him Ellie is wanting a bra. Sean feels this is a situation where a mother is needed to accompany her, but doesn't feel comfortable sending Ellie bra shopping alone. Liz offers to go with Ellie, but Sean wants to keep it a secret from his mother, Lorna since the two compete as it is for providing for Sean and Ellie.
Liz takes Ellie bra shopping and ends up getting her several wildly colored bras and a teddy, which Ellie is definitely not comfortable with. Lorna stops by and offers to take Ellie bra shopping. Sean hints to Ellie to keep it a secret that she previously went with Liz. She too also makes Ellie uncomfortable by asking Ellie about exploring her body and explaining as she gets older she will have "stirrings." Ellie ends up faking a stomachache in order to get out of the incredibly awkward situation.
Before Lorna and Ellie get back, Liz stops by with some shoes for Ellie and a bottle of wine. Sean tells Liz that Ellie was "deeply affected" by her bra shopping experience with her, but doesn't admit she disliked her bras she bought for her.
Lorna and Ellie walk in, to which Lorna explains what happened, and Liz asks why she took Ellie bra shopping after Liz took her. Lorna becomes upset that Liz was asked first instead of her.
Sean then explains to Lorna and Liz that at times Ellie will need both a mother figure like Lorna, and an older sister figure like Liz. After talking to Ellie he then decides that it's best he take her shopping himself.