Cut competition
Sibling rivalry can turn into a divisive habit. View your relationship with your parents on its own merits rather than comparing it with your sibling's relationship with them and you'll feel a weight lift. If your brother or sister stills wants to compete, that's their choice but it won't be half as much fun if you don't play.
Be constructive
If things seem to work out better for your sibling, look at why this may be. Is it true? If so, is it down to luck or do they persevere until they succeed? Use their success to motivate you.
I have a friend who worked twice as hard to beat his elder brother and ended up excelling at both sport and his career. Now, years later, they still compete with hobbies.
Cut them some slack
Conflict can become a habit - you expect it so you're quick to be defensive. Instead, spend a little time focusing on good points, which will affect how you act with them. Hopefully they'll pick up the good vibes and will be less antagonistic.
Develop your own talents
Value your own interests and things you do well rather than wasting energy focusing on them.
Don't rise to the bait
If you think he or she is purposely trying to draw you into an argument, stay calm, change the subject or leave the room. If you don't react, they'll get no satisfaction.
See their viewpoint
Try to see things from their perspective. If their behaviour is unjustly hostile towards you, its root is based in insecurity. Understanding it can help you feel less victimised.
Don't be bullied - or bully
Don't accept hurtful comments from a sibling that you wouldn't accept from anyone else. Criticising someone's behaviour is one thing but criticising their whole personality can seriously damage relationships.
Foster friendships
Just because you're related to someone, it doesn't mean you have a lot in common. Meet emotional needs through friends. Just keep family gatherings civil.
Keep control
You can't control how your sibling acts but you have total control over how you react. Just knowing this gives you lots of power.
Source: Daily Mirror