Castle: Hey, can I ask you something?
Beckett: Since when do you ask permission to ask questions?
Castle: It's about your mother's case. Have you ever thought about re-opening it?
Beckett: (Visually upset) What are you doing?
Castle: Nothing, I just thought if we worked together
Beckett: No!
Castle: I have resources
Beckett: Castle, you touch my mom's case and you and I are done. Do you understand?

Beckett: What is it with men and boobs anyway?
Castle: Biological. We can't help it
Beckett: But doesn't it bother you that they are so obviously not real?
Castle: Santa's not real, we still love opening his presents.

(Castle prom dress shopping with Alexis and Martha)
Castle: Sweetheart, I want you to know that no matter how you think you look, you are perfect exactly the way you are.

Castle: 'You look hideous'? Are you trying to give her body image issues?
Martha: Ohh! Newsflash. She already has body image issues. It's an intrinsic part of being a woman. Every woman in the world has some part of herself that she absolutely hates. Her hands are too small, her feet are too big, her hair's too straight, too curly, her ears stick out, her... (looking at herself in the mirror) Oh, God, her butt is too flat, her nose is too big... And you know, nothing you can say will change how we feel. What men don't understand is, the right clothes, the right shoes, the right makeup, just... it hides the flaws -- we think we have. They make us look beautiful... to ourselves. That's what makes us look beautiful, to others.
Castle: Used to be, all it took to make her feel beautiful was a pink tutu and a plastic tiara.
Martha: We spend our whole lives trying to feel that way, again.

Ryan: Get this. The hospital can't find the files. It's like it never happened.
Castle: Who did you talk to?
Ryan: Patient Information.
Castle: Weeeell, that was your first mistake. You want to find someone at a hospital who had a treatment there, there's only one department to go to where nothing EVER falls through the cracks...(everybody looks at him expectantly. With a sort of "duh" expression:) Billing.

Beckett: So what do we do, hop into a car and drive down to the bada bing?
Castle: I know a guy, he owes me a favor.
Beckett: "You know a guy"? What is this, a Mamet play?

Castle: Seriously? Parking Garage?
Beckett: What?
Castle: It's... pretty cliche.
Beckett: Yeah, well, no one said that the Feds were original.
Castle: Next thing you'll tell me they'll be pulling up in a black Suburban with tinted windows. (indeed, they do) Ohhhh, somebody's been watching way too many Bruckheimer films...

(Castle was sitting up waiting for Alexis to come home from the Prom. He turned his head away when they kissed goodbye)
Castle:Don't worry, I closed my eyes for the kissing part.
Alexis: Yeah, me too.

Kate: You look awfully serious. Is everything OK?
Castle: Take a seat.
Kate: What?
Castle: Sit down.
Kate: Castle, what's going on?
Castle: It's about your mother.

Kevin: Oh the terror of meeting my date's old man.
Castle: What did he do?
Kevin: Checked my wallet for condoms, showed me his gun collection. My hands were shaking so bad I could barely put on the corsage.

Castle: It's like she escaped from The Island of Dr. Moreau.

The Island of Dr. Moreau is an 1896 novel by noted SF author H.G. Wells, which explored the notions of humanity, cruelty to animals, and the distinctions between man and beast. It has been made into a movie three separate times, as Island of Lost Souls (1933, notable because it was one of the last movies released before the imposition of the Hays Code). under its original title in 1977, and again in 1996. It is also the inspiration behind the signature song Are We Not Men? (We Are Devo) by Punk/New Wave band Devo as well as the song No Spill Blood by New Wave band Oingo Boingo.

Beckett: C'mon, guys. She's not an animal, she's a human being.
Castle: Yeah, I know, but... wait are you being serious or quoting 'The Elephant Man'?

The Elephant Man is an award winning play and film about the life of Joseph Carey Merrick, an individual of the mid-late 1800s who suffered from a congenital defect that horribly disfigured him. In the play/film, at one point, he poignantly cries, behind the horrific visage, "I am not an animal, I am a human being!", calling clear attention to the fact that, behind the awful appearance was a living, thinking being with feelings like any other.

Beckett: You know a guy? What is this, a Mamet play?

David Mamet is a well known author, playwright, and screen director. He won the Pulitzer Prize for the play Glengarry Glen Ross, and among his other well-known works are the screenplays behind the films About Last Night... , The Verdict, and the 1981 version of The Postman Always Rings Twice. His films include State And Main and Things Change. Mamet also is the creative force behind the TV series The Unit. Mamet's dialogue, notable for its cynical, streetwise edge, carefully crafted for effect, is sufficiently distinctive that is often called "Mamet Speak".

Castle:Next thing you'll tell me they'll be pulling up in a black Suburban with tinted windows. (indeed, they do) Ohhhh, somebody's been watching way too many Bruckheimer films...

The Chevy Suburban is a very popular model of SUV, essentially a Chevy pickup truck with a station-wagon style body.

Jerry Bruckheimer is a noted film producer with more than 30 feature films to his name bringing in more than 13 billion dollars to Hollywood. As a result he is widely regarded as one of the most successful producers in history. His first major success might be considered Flashdance, and among the films which followed are Beverly Hills Cop, Top Gun, The Rock, Con Air, Armageddon, Enemy of the State, Pearl Harbor, and the Pirates of the Caribbean trilogy. Bruckheimer is also behind the wildly successful CSI television franchise, the original of which is still getting top 10 ratings even into its tenth year.

Castle: When I gave you that little speech last night I didn't mean for you to go all Beautiful Mind on me.

A Beautiful Mind is a book and an adapted film about the life of Nobel Economics Laureate John Forbes Nash. The film won four Oscars including Best Picture and Best Director. The story is about Nash's slow descent into paranoid schizophrenia. The story does take extensive liberties with the facts about Nash's life, however, which has been a subject of some criticism.

Title: A Death in the Family

The title alludes to the story in two ways, both through the effort of the mob to kill one of their own for turning "state's evidence", but also for the important tie-in of Castle's investigation of the murder of Beckett's mother.