Joshua

Joshua is the father of brothers Jake, Finn, and Jermaine. He and his wife, Margaret, adopted Finn as a baby. He speaks in a 1940s Mid-Atlantic accent. Joshua's personality is demonstrated as an old-fashioned manly dog who is willing to push his sons to fight, particularly when they need to.

History
Joshua first appeared with his wife in one of Finn's flashbacks in the episode "Memories of Boom Boom Mountain." They find Finn after he has soiled himself causing him to be stuck to a leaf. Finn claims to have cried for a whole day before anyone helped him. They are the second to stop, after a ladybug mum and daughter, and help the seemingly abandoned baby Finn. They take him to what is presumably their house and raise him as their own.

Joshua returns in "Crystals Have Power," where his ghost appears from beyond the grave encouraging Jake to fight back against the Crystal Guardians of the Crystal Dimension after Jake takes a vow of non-violence. Jake became upset when he remembered Joshua telling him that "Jake would hurt everyone." Jake also sees his brother Jermaine in his flashback. It should be noted that Joshua was trying to tell Jake that "Jake would hurt everyone... who is evil. Let me finish next time."

During "Crystals Have Power," Jake says "stupid ghost dad" when talking to himself out of frustration after Joshua says "Come on, punch them Jake. Punch everybody. Why not? Come on, why not!" Also, when Joshua brings Jermaine to see Jake, Jake asks him if he is dead, implying that Joshua is already dead (Jermaine was not dead, he and Jake were just dreaming at the same time).

In "Dad's Dungeon," Joshua makes Finn and Jake (through pre-recorded Holo-message player cartridges) explore a dungeon he made. The dungeon is filled with traps and monsters to toughen up Finn. Joshua puts Jake's family sword at the end of it as incentive to go through its trials.

In "Jake the Dog," Jake states that during his childhood, Joshua enjoyed making pickles and giving them to him.

In Jake the Dad, Jake wears Joshua's hat while caring for his own children. It is assumed that he kept it as a memory of him after his disappearance or death.

In "The Pit," Finn and Lady watched videos of Joshua finding and imprisoning Kee-Oth the Demon. Joshua also mentioned a chart in the video: "refer to my chart... ..."

In "Billy's Bucket List," it was revealed that Finn and Jake buried him themselves. The location is apparently behind something, but Finn is cut off by Billy's constellation before he can reveal exactly where.

In "Joshua and Margaret Investigations," it's revealed that Joshua, not Margaret, gave birth to Jake via a hole in his head caused by a shapeshifter. This left a scar "the size of a nickel" on Joshua's head, resulting in his decision to wear a hat for the rest of his life. Despite the circumstances of Jake's birth, both Joshua and Margaret decided to raise him as their biological son. They also mutually agreed never to tell their sons the truth about Jake's birth. At the end of the episode, Jake told Finn their parents never told him about the day he was born, indicating that Joshua and Margaret had taken their secret to the grave.

Death
Joshua is confirmed as deceased by Finn. He, as well as his wife Margaret have probably died prior to the events of Adventure Time. The cause of death is unknown. In "Dad's Dungeon," the hologram video shows Joshua being attacked by an Evil Monster, this may have happened while Jake was still a baby, since the last hologram shows him telling Finn he finished the dungeon. In addition, Finn and Jake did not know about the dungeon until that episode, and Finn mentions burying Joshua with Jake's help in "Billy's Bucket List," indicating that Joshua escaped the monster and died at some later date, also if the monster did kill him, it would raise a question as to how the tapes made it back home.

Considering that the tapes were in the attic of the treehouse, presumably hidden there by Joshua himself, it's likely Joshua died some time after Finn and Jake moved into the treehouse.

Furthermore, in the beginning of "Dad's Dungeon," Joshua says, "If you're hearing this prerecorded message, it means I've passed on, and my spirit sparkles guided you to its secret hiding place," which adds to the evidence that he is dead but able to send signals using his spirit.

Abilities
Although Joshua did not possess stretching abilities like Jake (which themselves were a side-result of Jake's unique birth), he was still a tough dog who created a reputation for himself in Ooo prior to his death. It can be assumed that he is a very capable warrior or extremely stealthy, as demonstrated by the fact that he was able to outsmart and break a piece of horn off Kee-Oth. Joshua was also able to capture various monsters, including the Evil Monster and put them into his dungeon.

Joshua is also proficient in other things such as knitting, which was shown in "King Worm." However, this may not be true, as he was only seen doing this in a dream. Joshua knows of at least one incantation, used to slough Kee-Oth the Demon whose blood is present in the Demon Sword. In "Dad's Dungeon," he seems to create "spirit sparkles." It is unknown if this is a unique attribute or if Joshua even created them at all. He apparently knows how to make pickles.

In "Joshua and Margaret Investigations", he shown to be quite acrobatic as he able to perform a flip while getting to the telemarketer.

Appearance
Joshua looks very similar to Jake except his fur is a darker yellow color when compared to his son's. He also wears a grey hat that resembles a fedora to hide a scar on his head that he got when he "gave birth" to Jake.

In "Joshua and Margaret Investigations", he wears a navy blue tie.

Quotes
Joshua/Quotes

Major appearances

 * "Crystals Have Power"
 * "Dad's Dungeon"
 * "The Pit"
 * "Joshua and Margaret Investigations"

Minor appearances

 * "Memories of Boom Boom Mountain" (debut, flashback)
 * "King Worm" (dream cameo)
 * "The Comet" (cameo)
 * "Whipple The Happy Dragon" (hallucination)

Mentioned or pictured

 * "Memory of a Memory" (photograph)
 * "Beautopia"
 * "Jake the Dog"
 * "Play Date"
 * "Billy's Bucket List"
 * "Everything's Jake"
 * "Jermaine"
 * "Take Her Back"

Trivia

 * Unlike Jake, he cannot change his size.
 * Joshua is right handed.
 * When Susan draws a picture of a Lub Glub, Jake says, "That looks like my father."
 * Joshua's appearance is similar to Jake; however, Jake is a lighter color of yellow.
 * Joshua appeared in "King Worm," where he is seen knitting with green yarn.
 * Joshua has grandchildren named T.V., Kim Kil Whan, Viola, Jake Jr., and Charlie, who are born in the episode "Jake the Dad."
 * BWuCbrUCcAE7GJi.jpga appears briefly in issue #22 of the Adventure Time comic book reading young Finn and Jake a story about Billy.
 * According to Jake in the episode, "Jake the Dog," Joshua had a pickling hobby, and would frequently share the pickles he had made with Jake. This has never been mentioned by Finn, either because only Jake had known about it, or it has just never been something Finn has had a conversation about.
 * Joshua and Margaret seem to have contradicting personalities; Margaret is overprotective, whereas Joshua pushes his kids to fight.
 * This seems to switch when it applies to each other or themselves, like in the episode, "Joshua and Margaret Investigations," Joshua is too over protective of Margaret, while the latter is stubborn and isn't afraid to fight.
 * This is most likely because in that episode, Margaret is pregnant with Jermaine, and Joshua explains that the two of them would not be able to handle the guilt of having their son be hurt due to their risky occupation. Though, Joshua does seem to be too overprotective, as his meticulous caution causes Margaret to become irritated with him several times. Because of his overbearing anxiety about their son, Margaret attempts to and successfully proves that she is fully capable, and that her being pregnant is not a setback whatsoever in their job field.
 * In the episode "Jake the Dad," Jake wears the same hat as Joshua's.
 * Jake wears this hat again in "Root Beer Guy" and "Summer Showers."