The tot weighed in at a whopping nine pounds, 12 ounces (4.43 kilograms) - and Kerr admits the "intense" pain she felt during the 27-hour labour left her fearing for her life.
She tells Australia's InStyle magazine, "I actually thought I was going to die at one point and left my body. I was looking down on myself - the pain was so intense. I kept thinking, 'How do women do this? But if other women have done this, I can do it too.' I was determined."
But Kerr insists her traumatic labour was worthwhile: "We spent every minute together, morning and night, for those weeks before I went back to work. He sleeps in our bed every night."