"Haven't you got a coat with you?" I ask Daughter Number One as we walk into the airport.

"This is a coat," she says.

"That's a jumper," I say. "It's October. You need a coat."

"It's a fleece," she says. "And anyway, I don't have a coat."

"Yes you do. Your mum bought you one last month."

"It's covered in cat hair. And anyway this is warmer."

Daughter Number One is going to Belfast for the weekend. To get drunk with her cousin. That is how it's been sold to us. I'm not so worried about that. Her other, older cousin and his fiancee are going to be there too. It's just getting her there that I am worried about.

We've worked out that it's been 10 years since Daughter Number One was last on a plane. That was for her aunt's wedding and age-wise she was in single figures. I am trying to explain to her what she will have to do when she leaves "landside" to go to "airside". [1]

For the last two days I've been trying to explain that she will need to keep her liquids separate. And that they can't be more than 100 millilitres or whatever it is. [2]

"Aren't we checking the bag into the hold?" she asks.

"No. That costs extra. I'm not made of money, you know."

I go to pick up her bag. I can barely lift it. She's a third my size and weight. How, I think, is she going to get it up the stairs on to the plane? We go to the desk and check it in.

"Now you go through security and then you walk all the way around to the gates and you've got to check what gate you're going to leave for. And then when you're boarding you'll need your driving licence. And you've got to keep your boarding pass until you get on the plane. It's got your seat number and …"

She looks at me. She is not taking this in, I think. Oh God, she's going to get lost. She's going to be wandering around Edinburgh airport lost and we'll never see her again.

She disappears through security while I fret.

I realise I have become a helicopter parent, hovering over my daughter even when she's not in my vicinity any more. "Landed," she texts, eventually.

She goes and meets her cousins, and her aunt and her grandmother. She goes shopping. She stays out until three in the morning in Belfast. She gets drunk. I don't see any of that. She's in her aunt's house and I know she will be fine. My sister is infinitely more capable than I am.

But I worry. I worry about her coming back. I worry about her getting through security or getting lost in Belfast International. I worry and worry until she comes through the arrivals gate on Sunday night.

"You OK?" I ask.

"Yeah."

And relax.

[1] Did you know it was called landside? I didn't.

[2] Being a man this ruling doesn't affect me so much. Though admittedly I have lost the odd tin of hair wax.