Slowly but surely, the manchildren of The Big Bang Theory are becoming grown-ups. Leonard (Johnny Galecki) and Penny (Kaley Cuoco) got married, Sheldon (Jim Parsons) and Amy (Mayim Bialik) moved in together, Raj (Kunal Nayyar) can talk to women now. But in Thursday's episode, "The Birthday Synchronicity," Howard (Simon Helberg) and Bernadette (Melissa Rauch) took the biggest step of anyone so far into full-on adulthood: Bernadette gave birth to a baby girl, Halley — like the comet — Wolowitz.

Melissa Rauch and Simon Helberg, <em>The Big Bang Theory</em>Melissa Rauch and Simon Helberg, The Big Bang Theory

The biggest event of the episode was the birth of the baby, but "The Birthday Synchronicity" was just as much about the rest of the gang. It's Amy's birthday too, and she wants to celebrate by getting some rare physical intimacy with Sheldon. Frustratingly, she keeps getting interrupted — first by Penny and Leonard alerting them that Bernadette is having the baby and they're going to the hospital, then by Sheldon when he gets mad that she went to the Wizarding World of Harry Potter without him, and finally by Raj, who's been kicked out of everywhere else for being annoying.

Raj had the biggest story of the night. Raj has known the baby's gender for a long time, which Howard and Bernadette have made him keep a secret from them since they want to be surprised, but he let it slip. The crew got to the hospital too early, so they head back to the Wolowitz's. Raj is filming a video for the baby to watch once it gets older. "Here's your daddy," he says, pointing the camera at Howard. "When he tells you he used to be cool, you can see he wasn't." Howard tells him to knock it off, and Raj says "someday she's going to want to see this," which elicits "oh!"s from the studio audience.

Raj tries to cover his mistake by saying "I said 'she,' but lots of things are 'she': boats, cars, whales — 'there she blows!'" Howard and Bernadette are furious.

Raj feels undervalued, which continues when the others are all reflecting on how far they've all come — except Raj, who isn't progressing as quickly in life as his friends.

But then when Halley is born, Bernadette and Howard give him a gift: he's the baby's godfather.

Of course, even with his solemn new responsibility, he can't help but gloat: "You hear that, Stuart?" he yells to his third-wheel rival (Kevin Sussman). "I've got a dog and a godchild! You've got nothing!"

So 10 seasons in, and The Big Bang Theory finally has a baby. The weird little wannabe lady's man is a dad now. This is a milestone that sets up more such milestones — Leonard and Penny could have a baby. Sheldon and Amy could get married. The writers could deepen Raj's character, because it's true that he's not progressing as quickly as the rest of them, and it's time for a major Raj storyline. But for now, let's welcome Halley Wolowitz to the world.

Oh, and fun fact about Halley: her gigantic crying voice is provided by Pamela Adlon, an excellent voice actress best known for Bobby Hill on King of the Hill, as well as her own excellent show, Better Things. It's pretty funny to have a celebrity special guest on and just have her scream.

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