While Kira is giving birth to the O'Briens' baby, Odo adopts an infant Changeling.
- Birth/Death Juxtaposition: One baby dies, another one is born.
- Bittersweet Ending: The baby Changeling dies, but it merges with Odo and restores his powers. The O'Briens' new baby is born, but Kira is saddened to not have a child of her own to hold.
- Both Sides Have a Point: Both Odo and Mora Pol ultimately are shown to have points in their arguments regarding raising the changeling. Eventually they do resort to Mora's more painful techniques, which finally get the baby changeling to alter its shape...but then it attempts to mimic Odo's face, showing that the more nurturing approach Odo had used earlier hadn't been totally wasted.
- Continuity Nod: O'Brien's absence during Molly's birth is referenced.
- Get Out!: When Miles and Shakaar start bickering the second time she's in labor, Kira tells them to leave. The midwife and Keiko back her up, but let them back in when Kirayoshi is about to emerge.
- Hard-Work Montage: Odo showing the infant changeling various shapes.
- Infant Immortality: Averted.
- Never My Fault: For much of the episode, Mora is unsympathetic towards Odo and says that the fact that Odo "is standing here whining about it" is proof that Mora was right. After the Changeling imitates Odo, however, Mora does admit he was mistaken.
- Not What It Looks Like: Worf asks Odo why he's talking to his drink, which is really the Changeling.
- O.O.C. Is Serious Business: Quark is suspicious of Odo being chummy with him, as it usually means that Odo wants something from him, usually a confession. It takes him a while to accept that Odo, for once, is genuinely happy.
- Open-Minded Parent/Education Mama: Odo and Mora basically become this. Odo, the open-minded one who doesn't want to push his baby blob too hard. And Mora, the guy who'd rather use tests to get the baby moving.
- Pet the Dog: A subtle one for Quark. He probably could have sold the baby Changeling, even if it was actually dead, to Starfleet for a ton more money, but instead he sells it to Odo for a relatively cheap price.
- "The Reason You Suck" Speech:Mora Pol: If it wasn't for me, you'd still be sitting on a shelf somewhere in a beaker labeled 'unknown sample.'
Odo: If it wasn't for me, you'd be a nobody. Starfleet wouldn't hire you to judge a science fair!
- Reset Button: It's hit in a particularly cruel way by having the baby changeling merge itself into Odo as it's dying.
- Rewatch Bonus: If you view this episode again AFTER seeing In Purgatory's Shadow, you'll know that Changeling!Bashir was in this episode and that despite being a changeling himself and possible knowledge of changeling physiology, his efforts to help the baby were not enough as the baby was truly sick with nothing more that he could do.
- Right Out of My Clothes: When Odo becomes a changeling again, he morphs into a hawk, leaving his uniform in a pile on the Promenade.
- Tempting Fate: Odo tells the baby Changeling that he'll never treat it the way he was treated. Seconds later, Dr. Mora walks in.
- Took a Level in Jerkass: Shakaar, who believes that his status as Kira's boyfriend outranks O'Brien's status as the baby's father.
- Starfish Aliens: A reminder that Changelings are this. You have to admire Rene Auberjonois' ability to act with such convincing emotion towards a glass of corn syrup.
- Yank the Dog's Chain: For once in his life, raising the baby Changeling has made Odo truly, genuinely happy - naturally, it dies. Best summed up in the way The Reveal takes place: Odo goes on a long, cheerful monologue to Quark about how connecting to the Changeling has not only made him feel better, but finally made him reconnect to what its like to be a Changeling and made his life as a solid seem not so bad... and then he immediately gets the call that the Changeling is dying.