Thought I post some more information about the characters in the show. I got the info from Wikia. This is about the YJ members and their mentors:
Kid Flash and The Flash:
The history between Wally and Barry has yet to be revealed, however it is stated that they are family, through Barry's marriage to his wife Iris, making him Wally's uncle. This relationship allows for the two of them to interact in a more friendly and less formal manner than the other sidekicks and mentors. However, while Barry is more laid back and easy going, Wally seems to get impatient with his mentor. Their over-all good relationship however, seems to be the result of the fact that their entire family is close as a whole. Their family seems to be aware of their powers and dual identies.
Miss Martian and Martian ManHunter:
Martian Manhunter is Miss Martian's uncle, and she only recently arrived on Earth from Mars. Martian Manhunter and Miss Martian are both Martians, seem to share a close familiar relationship. The Manhunter in particular seems protective of Miss Martian, often coming to watch her train and see how she is getting along.Martian Manhunter did not initially want to bring Miss Martian to be inducted into the Justice League with the other sidekicks (Robin, Aqualad, Kid Flash, and Speedy). When Speedy quit as Green Arrow's partner, Martian Manhunter said he was glad he hadn't brought her along. Nevertheless, when Batman formed the remaining sidekicks (plus Superboy) into the team Young Justice, Martian Manhunter brought her along to be their new teammate.
AquaLad and AquaMan:
Being the King of Atlantis' partner, Aqualad sees Aquaman as a ruler, a mentor and a father figure. He was saddened upon learning that his king had kept vital information of the Justice League from him. The two however have since then repaired their friendship and partnership, with Aquaman offering Aqualad advise on relationships, love, and duty.
Robin and Batman:
Although the exact history of Batman's relationship with Robin has not yet been revealed, it is implied that Batman (Bruce Wayne) took Dick Grayson in at a young age, and spent many years educating and training him in his role as Robin, making him the most experienced member of Young Justice. Batman's general opinion of Robin, although rarely stated vocally, is high. When working in the field, they behave as a well-oiled machine, able to anticipate each other's moves, actions and plans, without the need to vocally communicate with each other.Despite being his mentor, Batman seems to try and treat Robin as a partner, rather than simply a sidekick, hearing him out when he states his opinion and even conceding to his points should they prove correct or logical. Batman is very protective of Robin which villains use to their advantage; but they underestimate Robin's ability which usually leads to their downfall. He seems to also view Robin as a natural leader of the Young Justice team, but has not pushed him into the role.Despite his new duties as a member of Young Justice, Robin still lives primarily in Gotham and works alongside Batman when not on League Business
Artemis and Green Arrow:
Artemis is Green Arrow's new protégé, following Red Arrow's decision to go solo. Their history together is currently unknown, and from implications made by Red Arrow, her association with Green Arrow is a recent thing. However, despite her short time apparently working with Green Arrow, he seems to feel that Artemis is ready to work as a member of the Young Justice team. She and Green Arrow both claim that she is Green Arrow's niece, although this is in fact a lie, thus making their relationship somewhat questionable.
Superboy and Superman:
Superboy is Superman's genetic clone and is considered by many as his "son". During incubation at Cadmus Labs, Superboy was programmed to replace Superman if he died, or to defeat Superman if he "turned from the Light". Superboy respects Superman, to the extent that Aqualad was able to convince him to resist the G-Gnome's telepathic control by asking "What would Superman do?"Originally Superboy longed to meet Superman, although when they finally met Superboy was angered by Superman's initial reaction of surprise and near disgust at having a clone. After the matter was explained, Superman tried to show some support for him but failed and quickly excused himself. Superman has actively avoided Superboy and tried to push responsibility of him onto Batman and Red Tornado. Even when Superboy directly asked Superman to help him figure out the extent of his powers, Superman refused and quickly left. Batman explained to Superman by saying "This boy needs his father", but Superman insisted that he was not Superboy's father and left. Superboy has since made attempts to conquer his anger, e.g. by seeking out the help of Black Canary.