When he was small, only just walking, my son loved to be in the garden. At first stones and mud and sand fascinated him and later worms and snails. It was all a wonderful adventure. And as he grew, in those precious days before he started school, I think he loved to be alone sometimes too. No supervision made Richard brave and he began to own his garden.

I was so fond of his attempts at understanding his world. Exploring before asking, examining before being told – refreshingly unlike me.

Then one night Richard’s sense of adventure left me terrified.

My husband had installed a house alarm and we turned it on for the first time before going to bed - and then sometime in the night the alarm went off. I just thought it was a fault and wasn’t too worried and when my husband went to turn off the alarm I looked in on Richard.

His bed was empty.

You know that sickening feeling when all logic leaves you and fear squeezes every muscle. I can still feel it now. I ran downstairs and there, standing beside an open front door, was a very frightened little boy.

I hadn’t realised he had grown so much. He could reach the door knob if he stood on his wooden stool (the one he used for indoor exploring). He was too young to explain much but he told me he had done it before. He wandered round the garden and into the street and then returned to bed and never said a word. I’m not sure how many times it had happened, maybe only once. All he said was that he wanted to know what it was like to be out in the dark.

It was Richard’s secret and it felt cruel to have to take it away from him.

Children need to have at least one secret.