On average there are 361,481 babies born in the world on a daily basis. Every 1 in 1500 of these babies is born with certain, rare characteristics that categorize them as not typically male and not typically female. These individuals are called "intersex".
People who are born under the intersex category are just like everybody else; they are 100% normally functioning human beings. However, some of the infants who are born this way, mostly those with ambiguous outer genitalia, undergo surgical and/or hormonal alterations to create more "socially acceptable" sexual characteristics.
This is wrong. This is a purely cosmetic surgery done upon infants that is suggested by doctors and agreed to by the parents for an aesthetic purpose. The child has no say in the matter. This surgery is irreversible. Nobody has the right to alter another individuals' body without their consent, let alone before their even old enough to understand what is going on and give that consent.
As a parent, you only want what is best for your child. You never want them to have to be discriminated against or face stigmatization. I get that and I can see how this surgery would be justified for the parents in their mind.
These parents, though, need to keep in mind two things. 1. That everybody will face these obstacles at some point in their life. 2. They cannot protect their children from everything that the world has to offer. The most important thing that you can do for your child is supporting them and be there for them in their time of confusion and need.
Many intersex individuals will recognize that they are not truly the gender that they have been associated with at a young age. If their parents go through with this operation, they will have no choice to go back. They can identify with their true gender, but their body will never be able to be as it should or as they would wish.
You need to let the child decide. This is their life; their choice. If they want to have the surgery then they can. If not, do not make them. This is a right that they have as a human being.