Although in common usage particularly of religious people you are correct, Faithful Catholic.  Scientific definition begs to differ.  When a fetus is born and able to survive on its own, it is a child.  No one knows when personhood and ensoulment takes place.  For instance even the introduction of a sperm into an evacuated ovum that is then stimulated can cause a fetus that could grow and develop all  the way to term. So please understand that to say you Know too much about what is happening means that you know the Mind of our Great God.  No finite person can know that much information.  Scientifically, it takes birth for there to be a baby.  Therefore intrauterine life is referred to as a fetus.  Perhaps if the fetus survives past 22 weeks gestation, it could be termed a baby as it might be able to survive at 22 weeks in the best of neonatal ICU's the are seldom present anywhere other than in major universities.