Monday, January 11, 2016. 12:25 AM. Piedmont, California.

Mabel woke up to a ghostly sound and rat-tat-tat noises. She doesn't know what it is. Here in Piedmont, there is nothing paranormal, weird, or anything Gravity Falls-like that could scare her. So what is it?

After a few minutes and still unable to fall back asleep, Mabel got up and inched towards the window to see what is going on. What she saw calmed her down; it is just a minor hailstorm. Little pellets of ice bounced off the windowsill as the trees lining the street below swayed with the wind.

Mabel returned to her bed and tried to go back to sleep. However, the sounds of the eerie wind and the ice knocking her window are keeping her awake. In her mind, she knows that what is going on is harmless; but in her heart, she is still frightened.

Mabel got out of her bed and went into the hallway. She opened the door to Dipper's room, and found her twin sound asleep, with no sign of discomfort on his face.

The sight of her brother made Mabel feel better. She went in and gently closed the door behind her. Then she crawled onto Dipper's bed, buried herself under the covers, and pressed her face against her brother.

The sound of the wind and ice of the outside hailstorm seem to disappear when Mabel heard a familiar comforting sound from Dipper: his heartbeat. Mabel shifted her head closer to Dipper's chest, trying to get to the soothing beating that has comforted her for many years.

She doesn't know why, but Mabel feels she has some sort of strange attachment to Dipper's heartbeat and Dipper as a whole. She broke a slight smile as she tries to drift off, listening to the rhythmic beating of her brother's heart.

Friday, February 19, 1999. 10:05 AM. Highland Hospital, Oakland, California.

"Hey, there's the heartbeat!" the doctor moved the ultrasound yoke over Mrs. Pines' belly. However, she paused for a moment, as if she picked up something else; in fact, she did. After a moment, a smile returned to her face. "Actually, there are two heartbeats. You seem to be pregnant with twins, Mrs. Pines."

Recently Mrs. Pines had not been feeling well; every day she would vomit or feel like vomiting at least once. Mr. Pines felt concerned for his wife's well-being; after several days of the same thing happening, he took her to the hospital. But the sickness Mrs. Pines had been undergoing is actually a good sign; having children is what the couple had been hoping for. And it is a perfect shot too; Mrs. Pines is pregnant with two children.

"There they are!" the doctor pointed to two dark spots on the blurry black-and-white projection of the ultrasound. It is pretty obvious; Mrs. Pines is carrying twins.

The doctor squinted at the ultrasound image to get a better look. "Seems like there are two placentas, like the usual. These two treasures could be either identical or fraternal; we'll have to wait," the doctor turned back towards Mrs. Pines. "Well, if they happen to be fraternal...do you have a history of twins on your side of the family, Mrs. Pines?" she inquired curiously.

"I myself wasn't a twin," Mrs. Pines replied. "But my father had a twin sister. My mother's side of the family had no twins whatsoever…how is it possible that I could have gotten twins?"

"Getting fraternal twins can be hereditary," the doctor explained. "A father can carry the trait and pass it on to his daughter. Of course, the father would have no control in whether his wife would get pregnant with twins. He doesn't carry the baby."

"Two of my uncles were twins," Mr. Pines commented. "I still do not know if they are fraternal or identical."

"Well, even identical twins can generate some noticeable physical differences," the doctor responded. "They may be genetically identical, but what sets them apart at birth all ties down to gene expression."

"What was that?" Mr. Pines remarked confusedly.

The doctor laughed. "Either way, you should consider having twins a blessing. Congratulations, Mr. and Mrs. Pines!"

It had been more than two months since Mabel had attached herself to her mother. It is when she settled down that she realized that she is not alone; another ball of cells had attached near her as well. She is glad to have company with her.

For the first several weeks of her existence, Mabel had been listening to the heavy heartbeat of her mother. Her mother's heartbeat and the presence of her neighboring brother are her primary sources of comfort in the oblivion world of the womb.

However, at one point, about three weeks after she stuck to her mother, Mabel started hearing another heartbeat. It is much softer and timid compared with the heavier beats of her mother, but this soft beating is nearer to her, and therefore she feels a greater attraction to it. It is the heartbeat of her twin brother. From that point on, Mabel would always turn to the beating of her brother's heart whenever she feels distressed. Sometimes she feels like the only heartbeat she heard is that of her twin; her mother's heartbeat, though deeper and louder, gets completely ignored by Mabel at times.

For more than 8 months, Mabel sat in her mother curled up next to her brother. The two are separated by their own amniotic sacs, and are attached to their own individual placentas, but emotionally Mabel did not feel disconnected with her brother. His constant presence next to her, and the occasional tap on her nose by him, gave her a continuous feeling of security and love. And of course, there is her brother's heartbeat – the 24/7 lifeblood of her counterpart and the noise that keeps her baby dreams sweet.

Tuesday, August 31, 1999. 8:35 AM.

Mr. Pines is over at an animation studio up in Point Richmond, giving a technical advice presentation on how the company can enhance their software to produce better computer-animated films.

He was in the middle of giving his presentation to the top officials of the studio when suddenly the phone in the middle of the meeting table rang.

"Hello?" one of the sitting members picked up the phone. After a few seconds, he called Mr. Pines over.

"Mr. Pines, your wife has gone into labor!" the member exclaimed. Mr. Pines rushed over and grabbed the phone.

"My water broke! I…I…" Mrs. Pines is visibly in pain on the other end. "Y-Your dad and un-uncle are…helping…me…please come! H-Highland Hospital! Please!"

"I'll be there! Don't worry!" And with that, Mr. Pines hung up the phone, detached his laptop from the projector, and started packing up.

"You're going to become a father, Mr. Pines," one of the sitting directors said. "Congratulations."

"Thanks, Mr. Lasseter," Mr. Pines said as he put on his suit coat. "I'm really sorry for the inconvenience."

"We understand. Take care."

Mr. Pines rushed over to his car. He wanted to get to the hospital as soon as possible. Unfortunately, the I-580 has unusually dense traffic, which would only lengthen the drive.

"It's ten in the morning. How can the rush hour still be going on?" Mr. Pines said frustratingly as he tried to get pass all the seemingly slow-moving cars on the freeway while still maintaining below the speed limit.

Mr. Pines doesn't know how much time had passed by the time he arrived at Oakland's Highland Hospital. All he cares about at the moment is meeting his wife.

In the waiting room near the area that dealt with maternity, Mr. Pines ran into his father and Uncle Stan, whom had come over to stay at his place a few days earlier. They had been anticipating the birth of the twins.

"Robert, by boy, you're here!" Shermie got up from his seat. "Just in time!"

"Has Caskey given birth yet?! Is she all right?!" Mr. Pines asked frantically.

"We don't know," Shermie said calmly. "They wouldn't let me or Stan in. You're the husband. If you want to see your wife, just ask. I'm sure they will let you in."

Shermie told Mr. Pines what room his wife is in. He rushed over and knocked on the door, somewhat loudly and in an obviously panicked manner.

"Sir, there is a very serious matter going on in here!" the nurse who answered the door spat irritatingly at Mr. Pines. "So get the…"

"He is my husband! Let him come in…oh-AHHHH!" Mrs. Pines shrieked as she further dealt with the pain of giving birth.

Mabel is suddenly met with a bright light and a cold atmosphere. She is no longer in the warmth of the womb.

The sudden exposure to the unfamiliar and dry air is overwhelming for Mabel. She opened her mouth, and swallowed a huge gust. She screamed and started crying.

Everything happened all at once. One moment Mabel was enjoying her time in the womb, and then in the next she is out in the open being catered to by these monsters. She continued kicking and crying as the frustrated doctors – one lightly bruised as a result of Mabel swaying her legs around – cleaned her and placed her into a crib.

Her brother is nowhere to be found. All she wants is to be near him; to hear his heartbeat, the sound that keeps saying to her, "I'm right here. Everything will be fine."

Mabel's brother is feeling no different from Mabel. Still in the womb, he is wondering where his sister had gone. Several weeks after he was created, he also started hearing Mabel's heartbeat, and had also turned to it as his primary source of comfort. As the two continued growing, he made sure his sister was happy and content. He recognized Mabel as his twin sister the moment both of them attached to their mother, and she has since became very dear to him.

Mabel did not pay attention to what else is going on. She continued crying, screaming for her brother. She is in an unknown environment, and is seeing faces she has never seen before. As she continued weeping, wishing intensely to be next to her twin, she managed to pick up snippets of something.

"No, no, NO! The cord is around his neck!"

"He's turning blue!"

"Save him! He's lacking air! He's going to suffocate!"

"Shut up! Hurry and hand me the, the…!"

"Save my child, please! Save my wife!"

"I've got him! I've got him! There! Let him breath! Come on, little fella, you can do this! You've got your whole life ahead of you!"

Mabel then heard the sound of another baby crying. She immediately stopped crying herself; it is the sound of her brother.

Mabel's brother finally got his first gasp of air. He is crying just as intensely as Mabel had. He is frightened by all the hands handling him, and the only thing he wants is to be placed next to his sister. He has no idea where she is.

Very soon, Mabel's twin is placed in the space next to her. He is still crying. However, upon seeing his sister, he quickly calmed down. Within seconds, a small smile appeared on his face.

Mabel is put at ease. Her brother is fine, and is right there next to her. Getting separated from the other would be the last thing either would want; for months on end, the two had been living and growing side-by-side in the same space. Thus, they had been attached before birth.

Mabel inched her way closer to her brother. She pressed herself against him, and finally managed to find the sure sign of his presence: his heartbeat.

Mabel's brother pressed his mouth against Mabel's forehead; Dipper's very first kiss is for his sister, and the kiss is being placed right there on her forehead. Feeling deeply affectionate for her brother, a smile emerged on Mabel's face, and soon she is fast asleep. Mabel's snoring also put Dipper to sleep as well.

One of the nurses came by and picked up the two sleeping babies, and carried them over to Mrs. Pines. She is visibly worn out from having to give birth two times consecutively.

Mrs. Pines took her two children, and cradled one in each arm. She kissed the forehead of each one.

Mr. Pines is relieved; his wife is fine, his kids are fine, and he is finally a father. He continued standing next to his wife, happily watching his children snoring in her arms.

Monday, January 11, 2016. 12:40 AM. Piedmont, California.

Mabel is still half-awake, cuddled next to Dipper in his room. As she listened to his heartbeat, Mabel is trying to find out why she has such a strong attachment to it, a strong attachment to her brother. She does not want to ever get separated from Dipper.

Mabel's deep thinking and the steady beating of Dipper's heart is slowly putting the teenage girl closer to sleep. The two are already 16-year-old eleventh-graders, but their age doesn't stop them from wanting to hold their twin tightly for fear of losing the other.

Mabel felt an arm being put around her. She further pushed herself against Dipper as he pulled her in.

"I'm right here. Everything will be fine," Dipper whispered into his sister's ear.

The hail continued to pound the house, and the wind showed no signs of dying down. But Mabel cannot hear the sound of the storm anymore. All she could hear is Dipper.

Mabel felt Dipper's hand. She took it, lifted it to her face, and warmly kissed the palm. She squeezed Dipper's hand as she pressed it against her cheek. Mabel can sense Dipper shifting slightly, and his lips being placed on her forehead. Dipper has kissed Mabel's forehead many times before, but every time it happened, her "calm" button would have been pressed. She doesn't know why when Dipper kisses that particular spot she feels better almost instantly.

As dawn approached, the hailstorm had already longed stopped, and there are few clouds covering the sky. Being wintertime, the sun is still well behind the hills of the East Bay. The region continued to hold its sleepy and peaceful feel in the cold, early morning environment.

There is still some time before Dipper's alarm goes off, signaling the first day of his and his sister's first day of their junior year's third quarter and second semester. The twins are tightly pressed against each other under the bed covers, sleeping soundly. Mabel still has her head against Dipper's chest, snuggly tucked under his chin, while Dipper has one arm around Mabel, keeping her close. The two are holding hands and snoring softly.

Gravity Falls was created by Alex Hirsch and produced by Disney Television Animation. All characters and related media belong to Disney.

Highland Hospital is an actual medical center in Oakland, CA, off the I-580 and southwest from Piedmont.

Pixar Animation Studios is an actual film production company located in Emeryville, California; before their current campus opened in 2000, Pixar was located in Point Richmond, CA. John Lasseter is the former Chief Creative Officer of both Pixar and Walt Disney Animation Studios.