Ellie is old enough now to start wearing bras, but she's sensitive about the subject. Sean's pretty uncomfortable with the whole thing and knows he's really got two options: his overbearing, curmudgeon mother or his best friend, Liz, who's not blood but does seem to know a thing or two about breasts. Whatever route Sean goes, one thing is clear: someone's about to get her feelings hurt!
Sean airs his dilemma at work and Liz immediately volunteers for the shopping job. Sean says OK - but only if she'll keep it a secret. He knows his mom would be crushed to find out a stranger took her granddaughter bra shopping.
Sean's ever-nosy boss Max overhears and brings Sean a gift for Ellie: a bra. Sean is beyond uncomfortable with the idea of Max shopping for his daughter's underwear, but Max insists he not make things weird. Max explains that he wants Sean to work like a hamster on a wheel and that means not occupying his time or energy at work with home life concerns. In a further effort to boost productivity, Max bans Sean from the company break room.
At home, Ellie comes back from shopping dejected. The bra excursion started off okay but got weird quickly; Liz bought Ellie a ton of very seductive bras. Sean apologizes and agrees to let Ellie shop alone tomorrow, no harm no foul. And then harm enters! Lorna's letting herself in with her key; Sean scrambles to hide the bras, stuffing them hither and thither.
Of course, Lorna finds one of Ellie's hastily tossed bras in Sean's spaghetti pot. Sean compounds his secret by telling her Ellie went alone and bought inappropriate bras. Lorna offers to take Ellie the next day, and Sean agrees, again not wanting to hurt anyone's feelings. But later, at the mall, Ellie's time with Lorna is even more uncomfortable than her trip with Liz. Meanwhile, Liz drops in on Sean at home. When Ellie and Lorna return, Sean is mortified, fearing his secret plans will be exposed. Sure enough, Lorna and Liz find out they both took Ellie bra shopping. Sean tried to keep everyone's feelings intact, but it snapped back on him like a too-tight bra strap.
When Ellie's mother moved to New York, Lorna hoped that she could finally be there for her granddaughter and play a loving and important part in her life. Sean tries to please everyone by saying sometimes Ellie needs a grandmother, and sometimes she needs a bigger sister, like Liz. There's plenty of Ellie to go around... and there's plenty more brazzerially (it's a word now) every day! Sean apologizes to Ellie for mucking up the situation and promises to take Ellie bra shopping himself the next day.
The next day at work, Sean decides to teach Max a lesson by giving him one of the bras Liz bought Ellie - as a gift for his mother! Max finds it wildly inappropriate and mocks Sean for the blatant, silly attempt at retribution. And yet, Max appreciates the backbone Sean is showing; he decides he can use the break room again.