Adult Sheldon: I returned home from Germany to a family which no longer cherished me. But I knew somewhere I was still valued, where I was still the center of attention. And, most importantly, where I had my own bathroom.

Adult Sheldon: I didn't realize until years later that my father was only asking questions about lightning and thunder to cheer me up. In fact, he would often pretend to be dumb just to make me feel better.

Adult Sheldon: My father didn't always get the credit he deserved. The advice he gave me actually worked out pretty well. Of course, I never told him.
George: Talked to Billy.
Missy: Why would you do that?
George: No, it was good.
Missy: Stay out of my life.
Adult Sheldon: He may not have been the world's greatest dad. But maybe we weren't the world's greatest kids.

Pastor Jeff: Before our final prayer, would anyone else like to say a few words?
Mary: Missy? [Missy shakes her head] Shelly?
[Sheldon stands up and walks up to the microphone]
Sheldon: I've been thinking a lot about the last moments I had with my dad. It was morning, and he was leaving for work. He said, "See y'all later." And I said nothing. I regret that. I could have said "bye" or asked him for a ride. Or told him that I loved him. But I didn't. I barely noticed he left. So many times that I didn't notice my father. I hope he knew how much I loved him.
Adult Sheldon: I wish I could tell you I said all those things. But I didn't.
Mary: Shelly? [Sheldon shakes his head] [Mary shakes her head to Pastor Jeff]
Pastor Jeff: Let's bow our heads in prayer.
All: Our Father, who is in heaven, hallowed be Your name...
Adult Sheldon: For a long time, I focused on my father's shortcomings. Now that I'm his age and have kids of my own, I realize he was just a person doing the best he could, and he did a lot. I didn't say it at his funeral, but I can say it now. I loved my father. I will miss him forever.

Sheldon: Mark my words, string theory is going to be the next big thing.
Mary: What does it do?
Sheldon: It explains the fundamental forces of the universe. How everything works, where everything came from.
Mary: I know where it all came from. [points to the heavens]
Sheldon: Mother, we're in the sky. Why are you pointing up?

Sheldon: [baby crying] Babies. Why'd it have to be babies?
Mary: Oh, relax. He'll cry himself out. You won't even know he's there.
[four hours later:]
Sheldon: [baby crying] [sighs] Please tell that mother to quiet her baby.
Mary: Sometimes moms can't make their kids be quiet no matter how much they try.

[After a bout of turbulence, Mary clasps her hands together in prayer]
Sheldon: Oh, there's no reason to do that. It's just irregular motion of air around the plane caused by temperature changes. [more turbulence] Oh, that was a big one. And given our altitude, perfectly predictable. [cabin alert chimes]
Flight Attendant: [v.o.] The pilot has turned on the seatbelt sign. Please return to your seat.
Sheldon: A reasonable precaution. [checks seatbelt] Snug as a bug. [more turbulence]
Mary: Would you like me to include you in my prayers?
Sheldon: No, thanks, I don't need to seek help from an invisible man.
Mary: You're right, you've got your invisible strings.