I pulled out the bookmark and began to read. I was immersed in an absorbing autobiography. Suddenly I became aware that I was reading it in the genre of The Tiger who Came to Tea. I realised I had regressed into parent mode.

It’s been like this since Brat Minor, Catherine and Mini Minor set up temporary camp at Fortress H while they search for a house in Norfolk.

Spending time with our granddaughter has been a joy but the ageing memory does leave a bit to be desired. I can’t remember all the words to The Wheels on the Bus and arthritic fingers sometimes struggle with assembling Duplo.

When Brats M and M were tiny they would plead: “Can you play a game with me?” I still feel a pang of guilt that I would occasionally fudge an excuse.

“Rather busy now, so a bit later perhaps.”

That excuse doesn’t cut it these days. Retired and being a disciple of the philosophy 'Never do today what you can put off until tomorrow' means I have no reason not to play pairs, dig in the sandpit or read the exciting adventures of Dudley the dormouse.

The upside is, when Mrs H allocates me a task, I’ve been able to sidestep it. With a look as if there’s nothing I’d rather do than vacuum the stairs, I can say: "I would, but I promised I’d look after her for an hour.”

So, armed with a mug of freshly-brewed coffee I force myself to sit in the armchair and for the next hour or so supervise Mini Minor as she occupies herself serving imaginary breakfast to a cuddly rabbit, a floppy dog and a dinosaur. Apparently, they thrive on a diet of raspberries and peanut butter.

And I can offload the blame when things go wrong.

“Honestly, I’m not responsible for that stain on the carpet. It must have been one of them.”

When Mrs H first appears in the morning, the most I get is a salutary grunt - until she has had her coffee and toast. So, it makes a change to be greeted with an enthusiastic: “Hello Grandad!” followed by a tiny hand clasping mine and leading me to the north wing to read The Playing Story.

This is the tale of a child who uses his imagination to do all sorts of things to alleviate his boredom. I must do everything the boy does. I have to pretend to swim. To do this I am ordered to lie on the floor and thrash around as if I am swimming for my life.

I’m OK going down, but creaking joints slow my rise to the perpendicular and that’s got me in trouble for not being ready to strut round the room like a robot or perform my impression of a saltshaker.

There is one member of the new Fortress commune I haven’t yet mentioned.

You may remember from the previous dispatch that also taking up residence was the boisterous Dougal, the Labrador/Springer cross.

When he greets you, he is a bit like a jumbo jet taking off. He hurtles towards you elevating to his hindlegs. In full flight, he buries a cold wet nose into your face, gives you a good snuffle before bounding off to find his next victim.

Tail wagging, usually with a ball in his mouth, he clocks up miles patrolling the house keeping tabs on us all.

His appetite knows no bounds and throughout his plodding his nose is like radar, constantly scanning for anything edible. I dropped my guard the other morning and turned to see my toast vanishing out the kitchen door.

Well, I’m off childminding duties now, so it’s back to my book. Now where was I? Ah yes, here we are.

“The tiger said: ‘Excuse me, but I’m very hungry. Do you think I could have tea with you?’”