I have two sisters who are older than me. The eldest was a bully. She literally beat the hell out of me. My other sister was very popular in school. I was more of a misfit. I stayed out of her way, feeling association with me would harm her voguishness.
The Sun in your chart shows how you shine. If your Sun is exalted (in Aries), it’s not likely you’re going to have this problem. Sometimes the baby of the family is rock star, right? I’m just saying, it’s in the chart more than the birth order.
If you’re (unconsciously) stuck in the shadow of an older sibling, it’s bound to compromise your life.
Are you living in the shadow of your older sibling?