Theodore’s mother has four sons: North, West, and South. And who is that fourth son? Why, it’s Theodore, of course.
Theodore’s mother has four sons, North, West and South. Who is the fourth son? Indeed! It is Theodore of… The name of the fourth child is Stacy. You said her mom had 4 children and named the other 3. Stacy is the fourth!
It would be very clear to a native English speaker that someone means Theodore in this puzzle since he mentions his mother having only three sons earlier in the paragraph.
Now, instead of “Someone’s mother,” we have, “Theodore’s mother has four sons: North, West, and South.” And who is that fourth son? Why, it’s Theodore, of …