Shaving a babies hair or cutting a babies hair does not actually make the babies hair grow thicker.
Although when you shave your babies hair it makes the hair grow back to where the hair looks like it has grown back thicker.
But it's just an illusion and the hair is still the same thickness.
There's no need to shave a babies hair or cut a babies hair until they are at least 1 year old or above.
The hair when cut will not be any healthier than it would be if it had not been cut.
I never cut my babies hair until they were around 14 months to 18 months of age.
They never needed a hair cut any sooner than that anyway.
You're not gonna harm the baby if you do cut their hair before 1 year of age but it's not gonna do anything anyway.