The events of Despicable Me 2 mainly take place during April and May. Three weeks pass from the theft of PX-41 lab at the beginning of the movie, and Eduardo mentions that he'll pick up cupcakes for Cinco de Mayo "next week". It is unknown, however, in the movie itself, how much time passes between the AVL mission and Gru and Lucy's wedding. In addition, at least a year has passed between the events of Despicable Me and Despicable Me 2.
Some minions, like Kevin, are redesigned in this film. However, it is arguable that there are two or more minions with the same name.
The wig that Gru wears in his date is silmar to Floyd Eaglesan's hair, but the wig is black and Floyd Eaglesan's hair is blonde.
In Mexico, there is a magazine called Eres Niño (You are a Kid), where in one issue it is talking about Despicable Me 2 with information about the characters and when producing the film, with a double poster of Despicable Me 2 and La CQ (The CQ), pushout images, and a mouse pad.
The producers say that El Macho is related to a Mexican wrestler named El Santo. El Santo is a Mexican wrestler with a mask, cape, and suit that is coloured silver (like El Macho with his red and black clothing), only that El Santo isn't fat like El Macho.
When Phil the Minion is abducted, it is possible that the kidnapper is Dr. Nefario. This is likely because:
When the person that abducted Tom walked on the front yard, the shadow of the perpatrator had the shape of Dr. Nefario's head and it is not round.
When Phil opened the door, he smiled and greeted like if he knew the person, then he had a confused expression and he screamed like if the person is going to put him in a bag.
The necklace that Eduardo wears in the present-day is most likely the same necklace that he wore as El Macho twenty years ago, only worn sideways. It is returned to it's normal position when he reveals himself as the notorious villain.
In the film you can see that the gloves that Dr. Nefario wears has a "G" for Gru in a yellow path. The Minions have blue overalls with a "G" printed on them. When Dr. Nefario worked for El Macho, his gloves have an "M" that was printed red for Macho. Also, when the Minions turned into Evil Minions, El Macho changed their uniforms for black overalls with an "M" printed on them, but white.
In the first film, Gru has three flashbacks about his childhood dream of wanting to go to the Moon and his mother crushing his hopes each time. In this film, he only has one flashback about when he wanted to date Lisa, a girl from his school.
Vector is never mentioned in this film, but Gru may have used a piranha from Vector's piranha gun for the fishing pool in Agnes' birthday.
Seven books were published for this film like The Junior Novel, The Anti-Villain League Handbook, Undercover Super Spies, Attack of the Evil Minion!, Make a Minion, and Meet the Minions.
The Junior Novel reveals that the one hundred and forty-seven dates between the defeat of El Macho and Gru and Lucy's wedding take place over six months.
When Lucy used her Lipstick Taser on Gru, Gru dropped his Freeze Ray on the ground. However, in the next shot where Lucy is trying to carry Gru into her car, his freeze ray disappeared.
When Gru calls Dave and then Stuart during the ice cream party in Gru's Lab, Stuart reacts first while Dave is the second. It may be a mistake of the dialogue.
In the scene where Eduardo shows his chest, it has the Mexican flag, but after the scene, it is gone permanently.
While Lucy practices her Australian accent, she mentions Hugh Jackman, who is a real actor.
Agnes's Unicorn toy is smaller than her in this movie. It is possible that Agnes had a growth spurt.
During the end credits, there is a goof error in the music listing for "Scream". It reads, "Produced Pharrell Williams".
For the celebration of the release of the film, Glenn McCoy drew 12 strips with the Minions in the comic The Duplex; such comics started at June 24 and ended at July 6, 2013. Later, McCoy himself also became the director of the short Mower Minions, which was released in 2016.