They breathed in unison. All over the city, all over the planet, the bots were breathing together. They moved and walked and spoke as their individual programming dictated, but their breathing was synchronised, in and out with the constancy of a ticking clock. She was in her twenties when she first managed to make her own working robot and it breathed with inexorable regularity. In out. In out. In out.
"Hello," it said. In out. "Are you my mother?"
She laughed.
"The female creator of my form," it insisted, "The instantiator of my existence. Are you my mother?"
She had to concede that she was, although the term made her uneasy.
In out. In out. It breathed just like all the other bots did.

Without access to the research databases, she had made a very basic effort at its programming, and that meant it needed to be taught.
"Do I have a name?" It asked her, as she was showing it how to clean the windows. It was standing very close. She could hear it breathing in out, in out.
"No. Would you like one?"
It went very quiet as it considered the question, breathing in out, in out. The sound was beginning to irritate her.
"I do not know of like," it said finally, "But convention would dictate that a living being needs a name."
"You are not alive."
"I think I am. 'I think, therefore I am'," it quoted. "Did not an early philosopher of your people say this?"
"Maybe tomorrow," she told it.
The room was filled with the soft sounds of mechanical respiration; in out, in out.

The robot never slept, of course, so it would often spend the nights moving quietly through her rooms, cleaning and tidying and generally occupying itself. She found she became even lazier with the housework out of sympathy - she couldn't bear the thought of it sitting idle while she slept.
But no matter what it was doing or how hard she tried not to listen, she could always hear it breathing. When she was working at her desk, she could hear it. When she made breakfast, she could hear it. Even outside her home the sound was there, echoed in every bot across the city. In out - a robotic nanny escorted her charges across the street. In out - a mechanical doorman tipped his hat to passers-by. In out. In out. An artificially intelligent shopkeeper arranged goods in the display window. In out, in out! She couldn't take it anymore, that chorus of synthetic breaths bombarding her from every direction.

"Is something wrong?" Her creation asked as she stormed inside and slammed the door. In out, in out, in out.
"Stop that, stop breathing."
"Stop? But every living being requires the regular intake of oxygen -"
"Enough!" She shouted. In out, in out. Her tools were where she had left them that morning, carelessly tossed onto the workbench. She took the ones she needed without hesitation, ripping open the robot's chestplate and tearing at the tubes and wires that simulated the human respiratory system.
"You aren't alive. You don't need oxygen," she growled, as she slammed the casing shut.
She held her breath -
Ah... blessed silence.

After she had gone to sleep, the robot limped over to her workbench and stared at its innards lying amongst the tools. With careful hands it took them up, opened its chest, and began to repair itself. When the damage had been undone it gently closed the casing again, and breathed a deep sigh of relief.
In. Out.