I really only noticed after a couple of months had passed. I was busy at work, coming home tired.
What I did notice was that Mum would go out every second Friday night very smartly dressed.
She would return home late, sometimes looking a bit dishevelled and always depressed. As this was her only social activity I was concerned.
"Oh" she would say, "just visiting old friends."
Mum had me when she was quite young, so she still had a youthful figure and with her flowing brunette shoulder length hair and deep brown eyes she was sexy and pretty.
One of these old friends had a daughter I lunched with occasionally. We met one lunchtime.
I talked about Mum.
"You don't know?" said Maryanne.
"Know what?" I asked.
"Where she goes on those Fridays."
"See old friends, she says."
"Bit out of it, aren't we?"
"What do you mean?"
"Haven't you noticed? Tight dress, lots of make-up? She goes to a party."
"A party?"
Maryanne lowered her voice, "It's a mother daughter swap party."
I caught my breath, "A -- a what?"
"Mum's swap their daughters for sex."
"Really?"
"Yeah, it's super sexy and fun."
"You've been to one?" I was intrigued.
"Only a couple of times. My mum stopped going after she hurt her leg -- it got a bit, you know, too energetic for her."
"I -- I didn't realise."