I have a theory that you can tell which of your work colleagues grew up in large families – or lived in a hostel when they were in college – by the way in which they navigate the office kitchen or lunch room.

They are more aware of who is in the room with them

Several times at work I’ve walked into the kitchen and there’s been only one other person there. But, every time I try to do anything, they are magically in my way. And, if we don’t quickly settle on an unspoken protocol of how we’re going to successfully navigate around each other for the next two minutes, I can tell they come from a small family.

Sure people from large families get in each other’s way when they’re in the kitchen. But how quickly and automatically they adjust to the presence of others is what sets them apart from people like me: a person who grew up in a large family and, in my specific instance, also spent several years in a hostel and shared apartment while at university.

They are more comfortable working around a single sink

The kitchen in my corner of the office has just a single sink. This sink has two taps: one for washing dishes and one for getting boiling hot or refrigerated cold water. Some people are comfortable with this arrangement, some people aren't.

When I’m washing dishes, for example, I’m have no problem moving slightly to the right to give someone the space to squeeze in next to me and fill their water bottle from the other tap. That's because I come from a large family and sharing sinks is something you have to get used to pretty darned quickly. So, if I’ve finished stirring my cup of tea and just need to rinse my spoon, and the person doing their dishes pauses for two seconds so I can run my spoon under the water, I know they come from a large family.

The best are those moments in which one person is washing their dishes, another is filling their tea cup, a third has just rinsed their fork, a fourth is reaching for a plate from the dish rack, a fifth is wiping a spill on the counter next to you, and a sixth is waiting for the slightest opening to stick their hand in and drop their spoon into the sink. That’s when I want to burst into song with a heartfelt “We are family / I got all my sisters with me” :)

They adjust more quickly to new situations

All this doesn’t mean that people from small families don’t learn and adjust. They do, and they adjust quite well. But you can still tell which people have learnt these skills in the office and which of them have had a childhood in which they shared a kitchen with their parents, grandparents, aunts and uncles, older and younger siblings, older and younger cousins, friends and, sometimes, pets.

Like when there are suddenly ten people in the kitchen at 3pm trying to make themselves a cup of tea or use the coffee machine. Some people will adjust automatically to this new situation – seemingly without any additional effort. But a couple will always take a few extra seconds to pause, observe and figure out how things are working before they’ll correctly read and then join the traffic flow.

That’s my theory anyway.