An expert has stated that first-borns dominate the family spotlight and get their parents' full attention at this time. Linda Blair said that sibling rivalry can start as a teenager when the younger sibling looks back and finds it unfair that they are not getting the same attention. She wrote in The Daily Telegraph: "The more they are the same, the more likely they are to get a sibling rivalry.

"If they are close in age, and especially of the same sex, they have similar needs at similar times and try to displace others so that their parents look after them first."

Ms. Blair said that as parents strive harder to meet each child's needs, "these feelings of rivalry will be less pronounced."

Sibling rivalry is less intense when the age difference between the two is more than four years.

She said, "If the age difference between two siblings is double-digit, as is the case for Charles and Andrew (there are more than 11 years), the sibling relationship usually has a very different quality.

"The couple is less likely to become equal companions.

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"It's less likely that you want to be the other when the age gap is so big."

Due to the great difference in age between the two brothers, Prince Andrew could be considered a "second-born" and accept many characteristics of a first-born.

She said, "First-born tend to be more competitive, so chances of a rivalry of a" second-born "who wants to take on the position of head of the family are more likely.

"This would explain – for me anyway – why Andrew might want to be like his older brother, much more than because he was constantly shut down in the hierarchy of the Monarchy."

However, Ms. Blair argues that Andrew wanted to be as if he did not want the same power and responsibility.

She said, "Sibling rivalry is more about the process than about the condition, more about attention than about a specific role.

"One sibling wants to become like another, to be seen as the" special "that is envied in the eyes of others."