Each book in a library has its own story to tell, they are unique in their way–some can be easily torn, others are hardbound, some were ruined already, and others were new, however, they are the same books that are valuable. This is the same with humans–they have their own stories to tell, their viewpoints, mindset, and beliefs, and have their ways of dealing with things that are thrown at them.
Every human is a unique being. Our experiences, social roles and norms, conditioning, and environment contribute to who we are today. In a circle of friends, each one has their personality and attitude and this applies even in a family like siblings. Your child is different from you or your other children. It is impossible to compare in the way of looking down on one of them just because someone excels in a more competitive field.
Humans are like books. You don’t know what they are going through, so you should handle it with care as that book could have a trauma—a very bad experience from others. Being kind doesn’t cost anything.