Mr. and Mrs. Pines

Mr. and Mrs Pines are the unseen parents of Dipper, Mabel and Sage Pines.

Early life
They have been raising their twin children, Dipper and Mabel, since birth. Their mother would dress Dipper in a lamb costume and have him perform the Lamby Lamby Dance when he was young. At one point in the twins' childhood, their father returned from a Windows '95 conference (likely related to his computer-based occupation), and received a promotional bag containing a t-shirt. Lacking the intention to ever wear it, he handed the shirt down to Mabel, who now uses it as a sleep shirt.

Season 1
Early in the summer, Mr. and Mrs. Pines agreed the twins required some "fresh air," and sent them to Gravity Falls, Oregon to stay at their great uncle's house in the woods.

They are only briefly (and partially) shown in "Tourist Trapped," their arms and torsos showed as they trade their son and daughter's video games and cat for luggage and sunscreen.

Mabel mentions their mother in "The Inconveniencing," recalling that she used to dress Dipper up in a lamb costume and have him perform the Lamby Lamby Dance.

In "Double Dipper," Wendy mentions she always assumed Dipper's nickname was derived out of his parents' hatred of him.

Both parents are briefly mentioned in "The Time Traveler's Pig," when Blendin Blandin threatens Dipper and Mabel by saying he will go back in time to prevent their parents from ever meeting. Because they still exist, the twins conclude that he forgot.

The twins' father is mentioned throughout "Fight Fighters" by Rumble McSkirmish, who believes that Robbie killed him; however, it is made clear by Dipper that this was a lie and that their father is, in fact, alive and well.

In "The Deep End" Mabel shows Mermando a picture of the family kickboxing.

In "Gideon Rises," Stan tries to reassure Dipper and Mabel's parents over the phone that their children are doing fine, claiming that they are staying at a four-star hotel, though they are actually staying at Soos' abuelita's run-down house.

Shorts
Mabel mentions their mother in "Mailbox," as she wishes to send her a video of her sticking one hundred gummy worms up her nose.

Season 2
They are mentioned in "Dungeons, Dungeons, and More Dungeons," when Mabel is writing a letter to them, describing how her and Dipper's summer in Gravity Falls has been so far.

In "Dipper and Mabel vs. the Future," they are mentioned when Ford tells Dipper that his parents would be thrilled that he could give Dipper an advanced education as his apprentice.

In "Weirdmageddon 3: Take Back The Falls", they are mentioned again when Mabel says that her parents wouldn't let her have Waddles at their home. After seeing Mabel's tearful goodbye to her pig, Stan demands that Waddles go home with her, saying that he put up with the pig all summer, so now it's Dipper and Mabel's parents' turn.

Personality
Mabel and Dipper's parents believe themselves to be slightly counter-culture, and purposefully chose somewhat archaic names for their children just so they'd stand out among more common names at the kids' preschool.

Season 1

 * 101. "Tourist Trapped" (no lines)
 * 105. "The Inconveniencing" (mentioned)
 * 107. "Double Dipper" (mentioned)
 * 109. "The Time Traveler's Pig" (mentioned)
 * 110. "Fight Fighters" (mentioned)
 * 120. "Gideon Rises" (mentioned)

Shorts

 * 3. "Mailbox" (mentioned)

Season 2

 * 212. "A Tale of Two Stans" (mentioned)
 * 213. "Dungeons, Dungeons, and More Dungeons" (mentioned)
 * 216. "Roadside Attraction" (mentioned)
 * 217. "Dipper and Mabel vs. the Future" (mentioned)
 * 220. "Weirdmageddon 3: Take Back The Falls" (mentioned)

Trivia

 * Dipper and Mabel's middle names are their parents' first names, like Alex and Ariel Hirsch. Though, neither of their middle names are mentioned throughout the series.
 * Since Stan shares the same surname as Dipper and Mabel, it can be inferred that he is the uncle of Dipper and Mabel's father.
 * Dipper and Mabel's father's occupation is related to computers.