Violet is back. She's overwhelmed at how much Lucas has grown. Addison is overwhelmed by the fact that the mother of the baby she's come to love is standing before her. She has no choice but to hand over Lucas after Pete asks Violet if she'd like to hold him. The look on Addison's face is one of fear, worry and heartbreak.
Addison asks the still-visiting Amelia to act as a consult for Carl, a soldier home on leave who recently passed out. When Amelia speculates that Carl may have a heart condition, his pregnant wife, Lucia, hopes they find something that will end her husband's tour of duty. Sam determines that a stent will fix him up good as new, which means Carl would be able to return to combat.
Cooper, Charlotte, Sam and Sheldon all welcome back their long lost friend. Violet tells them that she's had a very therapeutic breakthrough that finally brought her back home. She says she's ready to be Lucas's mom. Meanwhile, Amelia sees the fact that Violet is back as an opportunity for Sam to fight for Addison. Amelia's a bit of a buttinsky.
Carl the soldier is adamant about having a surgery that would allow him to get back in action. Sam is conflicted during the operation when a complication arises with multiple solutions. The most logical would be something that could allow Carl to return to duty. The second option would end his days in battle. Sam opts to do the latter. Afterwards, he tells Carl that even though it's not what he wanted, the fact that he gets to be with his family is what most people fight for.
A boy named Oliver has been eating unusual items. His mom, Kelly, and his stepdad, Scott, have taken the extreme measure of locking his head in a mask to get him to stop. Cooper suspects Oliver has a medical disorder called pica, which gives people an appetite for non-nutritive items. Sheldon confirms that the boy has pica. Cooper seems unusually uptight about the case. Sheldon suggests it's because of his own personal issues.
The truth is that Cooper is still dealing with his feelings for Charlotte. A near-miss kiss at her place sends him heading for the hills. But there seems to be something else going on. Cooper is highly-critical of Oliver's mom when she appears to be more interested in pleasing her new husband instead of helping her own son. He later discovers that the mom has pica, too. She's been hiding it for years.
Oliver is mad at his mom for lying to him. Cooper knows how he feels. He relays a story about how his parents had a son for eight years before they adopted him. Their first son died, which made Cooper feel like he was a replacement. He suggests that Oliver forgive his mother because he never forgave his own parents, and that didn't really work out for him. His words look like they've hit home with Oliver.
Violet tells Pete that she wants to work out a schedule to transition Lucas into her care. Pete immediately goes on the defensive, reminding Violet that she gave their baby to him and left. He says there's no way he's going to let Lucas be part of her therapy. Their little chat does not end on a high note.
Addison tells Sam he did the right thing regarding his decision with Carl the soldier. Sam says he's sick of doing the right thing. Guess that's why he takes Addison in his arms and kisses her passionately. Unfortunately, Pete walks in on them. Pete's had enough. He says to Addison, "Choose me or don't choose me, but I'm not gonna wait around." So the question is: Who will Addison choose?
Cooper stops by to ask Violet if the situation with his parents may have been why he was feeling like Charlotte's second choice after learning she was married. Violet says that makes total sense. Whoa, looks like he's had a breakthrough, too. Violet thinks Cooper should try to get Charlotte back. Then she asks him if she should try to get Lucas back. Violet says, "I'm gonna sue Pete for custody." Uh oh.