Lightbulb was declared the captain of the Bright Lights for winning the first challenge. As a result, she has had many interactions with her team members. While she has conflicts with some, a vast majority are positive interactions. Due to being captain of the Bright Lights, she usually guides everyone through the challenges, but due to her foolish nature, she can sometimes make the team lose.
Apple and Lightbulb appear to have a stable friendship. In Episodes, they do not have a conflict, but they do have some interactions. Lightbulb appears to have a neutral relationship with her, but Apple seems to think that Lightbulb has a bigger authority over the team.
In Marsh on Mars when Marshmallow is sent to Mars, she tells Lightbulb of Box's actions. (Cherries blamed Box for their actions). Lightbulb deals with this and puts Box in the Calm Down Corner, with Apple questioning if that's harsh, Lightbulb disagrees and says the punishment is suitable.
Later, when Apple volunteers to go to Mars to save Marshmallow, Lightbulb has no objection to this.