DOCTOR: Even as a child, my gift [for investigation] was well-developed. With the use of pure logic and observation I deduced where babies came from.

Peri yawned, hoping it would distract the Doctor from his fantasy. But if he noticed he didn’t respond, continuing as though every word was true.

DOCTOR: My mother had always insisted that the stork brought babies, but living in a large city I found that difficult to believe, as the arrival of infants was frequent but the sighting of storks was very rare. In fact, it wasn’t until the age of ten that I saw my first stork - and that was in a zoo! So once and for all I decided to solve the mystery. Word had it that a baby was due next door, so I set about watching our neighbour’s house. Apart from someone called a mid-wife, no-one else entered or left that dwelling until I heard the cry of a new-born babe.

PERI: No stork either, huh?

DOCTOR: Not even a sparrow. Now it had not gone unnoticed by me that the mid-wife had arrived carrying a large satchel. She had no sooner entered the house than I had heard an infant crying. I therefore deduced that the mid-wife had brought the baby in her bag!

A bemused smile spread across Peri’s face.

PERI: Brilliant. A very clever deduction for an unenlightened child.

She paused. The look on the Doctor’s face told her that she had said the wrong thing.

DOCTOR: So I was wrong on that occasion! I couldn’t help it if my idiot parents had refused to tell me the facts of life.