Unfortunately Nado is wrong in this one too. By Faith, we know that the human soul is created at conception. The fact that it is the substantial form of the body was defined as a dogma of faith by the Council of Vienne in 1311.
Since the soul of man is rational, it was a theological conclusion, supported by the definition of Vienne, that the soul is therefore spiritual and thus requires a special creative act by God (in whose image and likeness we are made) to bring it into existence as the form of the body at conception. Thee composite of body and soul make man, who is a rational animal, a complete substance with a rational nature. With the definition of the Immaculate Conception, it is now de fide as to the moment when the rational soul is created — at conception.