My gran, born in the 1920s, had a song for everything. There wasn’t a question you could ask or a line of conversation you could open up that wouldn’t trigger some long-entrenched musical memory and spur her on to do a bit of loosely-related warbling.

‘Cup of tea, gran?’

(starts warbling) ‘Oh, a tea in the morning, a tea in the evening, a tea around suppertime…’

‘You need me to take you to the shops, gran?’

(starts warbling) ‘Oh, and when we start shopping, we all start bopping, it’s off to the shops we go…’

‘You got the tests back from your anal scan yet, gran?’

(starts wabbling) ‘Ohhh, first you had a look, and then you took a snap, oh, you captured me deep inside…’

I think at least part of the reason for this habit was that singers in her day tended to sing about a greater range of life experiences, which gave music a sort of blanket relevance to daily life. Let’s face it, most songs these days are about shagging. And money. And how money can best help us with our shagging. But back then? Anything went. They wrote songs about the maddest and most inconsequential of shit.

‘Ladies and gentlemen, live from The Apollo Theatre in London, I urge you to turn your radios up as loud as they can go for the smooth, sensational stylings of Jimmy Foster and his Underwater Stockinged Turtle Band, performing their latest hit song, “The Blue Umbrella is My Favourite One, But I Guess the Yellow One is Sort of Alright, Too”.

Singers back in the 30s and 40s seemed to get their inspiration from the most banal of places. They would wake up, see a fallen cornflake half-crushed into the kitchen floor, rush to their phone, call up one of their band-mates and say, ‘Dave: get the guitar pronto, I’ve got a belter on my hands here!’

‘I mean it, Dave, this one has potential to be bigger than “Tuesday is Haircut Day, But Only Once I’ve Been to the Butcher’s”.’

Part of my gran’s habit was an age thing, of course. I’ve noticed similar behaviour in my mother in recent years, especially when she’s talking to her grandkids. She’ll start singing some old-timey song about biscuits, and they’ll just stare up at her in timid, slightly bemused silence until she stops, and then carry on blathering away as if it never happened, like the aural oddity was nothing more than a waitress dropping plates in a restaurant, or the cat farting.

Maybe they think their gran is sometimes possessed by the spirit of a deceased musical nutcase, but if they do their faces never show it. Kids are cool that way.

It’s all got me to wondering… What songs that are only tangentially related to the reality around me will I be singing to my grandkids in years to come (if luck should spare me long enough for that to happen)? I dread to think, given the amount of awful pop and dance music, and good but explicit rock and rap music to which I’ve been exposed in my life.

‘Grandpa, is there a time limit on us playing this virtual reality game?’

(starts warbling) ‘No, no, no, no, no, no – no, no, no, no – no, no THERE’S NO LIMIT!’

‘Grandpa, I don’t understand this riddle.’

(starts warbling) ‘Here is something you can’t understand (makes fist into a microphone). HOW I COULD JUST KILL A MAN!’

‘Grandpa, will you come through to the living room for a moment, please?’

(starts warbling) ‘FUCK YOU I WON’T DO WHAT YOU TELL ME!’

But, here’s the thing: I’ve already started riffing out songs to the young uns. Not my grandchildren, either. My own infant children of 3 and 5. The disease has kicked in a generation early for me. And here’s the other thing: none of the songs I sing to them – spurred on by the things they say or the questions they ask – are actually real songs. I make them all up.

‘Dad, can I have some toast?’

(starts rocking out) ‘Woooahooo, toast, toast, the way it feels, the way it feels when it’s in my mouth, I said TOAST, woooahooo, crunchy sometimes but buttery too, oooooooh hooo hooo, you gotta get that ratio RIGHT, girl!’

Only the other day I went off into a big number about the importance of putting your dishes in the sink, and my eldest son, Jack, said to me, very earnestly: ‘Who sings that one, dad? That’s a good one.’

He looked visibly impressed when I revealed that lying behind the surprise smash-hit of the season was his own father’s noble artistic vision.

I’ve got a theory: because my sister and I identified quite early in our lives this tendency in our elders to free associate the minutiae of life with music, it’s quite possible that I have internalised the jokes we used to make about it so completely that they’ve been written into my subconscious as code, and now the joke has become the reality.

But here’s another, rather more unsettling theory: If I’ve been making up all of these songs for my kids, then maybe my gran was doing the same. Maybe none of those songs about sugar, or bacon, or shirts, or daffodils actually existed, and she was just fucking mental?

Like I am.

I’m scared to look back at Frank Sinatra’s or Sidney Divine’s discography in case there’s a Kaiser Soze moment, and I discover that all of the old crooners’ songs were actually about money and shagging, and not biscuits and cups of tea like I was led to believe?

The truth is out there, people.

I think I know a song about that.

(starts warbling the theme tune for the X-Files)