If, counter to your hopes, you got a second son instead of a daughter, would it be OK to turn the boy into a girl as long as the offspring has not formed its own identity?

Also consider the sex change at different stages.
You could do it while it was still an embryo, a fetus, or right after birth, via surgery, hormone and/or gene therapy.
What other changes or enhancements would you be willing to consider (cybernetic implants, additional limbs and organs)?