Sibling rivalry is as normal as the sun rises in the east and sets in the west. This is especially strong when kids only have a small gap in their ages. Sibling rivalry can be a manifestation of jealousy or competition among two siblings, and can happen as soon as a new child is born into the family. Usually, this progresses from fighting about toys, to getting attention from parents, and then to more serious things as children grow up, like career paths and material possessions.
Dealing with sibling rivalry can be complicated. However, you can start solving this by keeping a few simple concepts in mind.
Sibling rivalry is usually caused by the feeling that parents have unequal preferences or give unequal attention to children. A toddler might be jealous of the time you spent caring for an infant, for example. Or a grade-schooler can be jealous of the freedoms you give his older brother or sister in high school.
The most basic way to minimize rivalry is by not comparing children, ever, and by giving them equal attention. You should also not take sides, as this will make them feel you have favorites. It’s also a good idea to let children cooperate instead of compete. This reinforces the idea that they should not fight for attention, but help each other do good things.