My dad doesn't know how to flush the toilet

It's about 20 minutes after lunch, and my parents want some coffee.  They're visiting me in the city and would rather - or, I would rather - go out for some than make it at my place.  Three hours in a small, enclosed space, and it's time to get some fresh air.

Before heading out, my father tells my mother and me he has to go to the bathroom.  Fine.  It shouldn't have to be an announcement, but with him, it usually is.

While my mother and I wait, we can hear muffled words from the bathroom.

"What is your father saying?" my mother asks.

"Wait.  Did he not shut the door to the bathroom?" I say aloud to no one.

"Did you shut the door to the bathroom?" my mother yells upstairs.

"Why would I shut the door to the bathroom?" I can hear my father bellow from above.

"Just watch," I tell my mother, "he probably didn't even turn on the fan."  He has a habit of not turning it on because it wastes electricity.  "Could you at least turn on the fan?"

"Why?  We're all in the same family," my father says.  I'm not sure if he's disgusted by the thought or insulted.  I, on the other hand, am both.

My mother and I hear the toilet flush and think he's done.  Then, we wait a few minutes.  And a few more minutes.  The water is still running.  I start to worry.  God forbid there's an overflow issue.  Reflecting on personal history, it's happened to my mother two times when she visited (not because of her, but of the internal mechanism malfunctioning).

I start to walk up the stairs.  "Dad, what are you doing?  Why is the water still running?"  I can hear the filling of the tank.

"Ugh, your toilet doesn't work." I can see my dad leaning in front of the toilet with his hands on his hips.

"What did you do?"  What I really mean is how much did he do.  Peeking into the bowl, there's nothing in there but some toilet paper.

"It doesn't flush."

"Of course it flushes."

"No, it just swirls." He'd been pulling on the mechanism for at least two minutes.

"It's these low-flush toilets," I point to the toilet.  "They don't have that woosh that older toilets have.  And because I'm on a lower floor, I don't have gravity to help push things down."

"You and your house."  My father shakes his head in disappointment.

"It's my fault the toilet doesn't work?"  They're always blaming me for things beyond my control.

"It's your house, isn't it?  You chose it, you live in it."

"I didn't choose the toilet."

"Hmph." My dad puckers his lips.  "You need to get a new toilet."

"It works fine for me." I raise my eyebrow.  "Are you going to buy me a new one?"

"This isn't my house!"

"Well, don't complain.  Or next time, don't use the toilet."

"Are you two done up there?" my mother yells from downstairs.  "Are we getting coffee, or not?"

After the toilet tank finishes refilling, my father and I head downstairs.  My mother is waiting with her coat on by the door.

"What was that all about?" she asks.  "You two were up there forever."

"Dad doesn't know how to flush the toilet," I reply.

"What?" She's not sure how to react.

"Don't ask." I quickly throw on my coat and push them out the door.  After what happened in the bathroom, I need some caffeine and a croissant.