I am seeing double

and double double this morning. 
No, don't panic. I think my eyesight is all right. It's just that there are suddenly twins - all over the front page of the paper...and then some more inside.
It's one of those "human interest" stories that caused the problem. There was a "first day at school" story about eight sets of twins starting in one school and six in another. There will be more elsewhere.   IVF technology has given a rise to the number of twins being born - at least here.
I know IVF twins. Their parents went through five cycles of unsuccessful treatment before they were born. There won't be any more children. They can't afford it and there is no chance of them conceiving naturally. Their mother has told me that she  is very glad there were two of them. She doesn't like the idea of an only child and believes they don't learn to share and socialise as easily. There are varying views on that.
The girls are not identical of course but they are clearly sisters. They are being encouraged to be individuals. They have different interests and even different friends at school. They are close but they don't have that unique "twin" sense I have observed in identical twins.
I knew someone who hated being a twin. She was a grown woman when I met her.  The first time I heard her speak she was saying angrily to someone , "Can't you imagine how awful it is to sit down at the breakfast table and look at yourself?" She had nothing to do with her twin.
I baby sat twins for three years through teacher training college. I needed the money but did I earn it! They were naughty little boys who revelled in being identical twins. They did everything together for years. They had their own unique means of communication. They could sit at the table and hold an entire conversation which was completely unintelligible to their parents. Told to talk like everyone else - because they could - they would simply become silent. Years later I asked one of them why they had almost never used their twin language in front of me.
      "We thought you understood it," he told me.  No, I had simply been fascinated by it. I am still fascinated by this strange ability. Not so long in the shopping centre I saw other twin boys of about five signing to one another. I know they are not deaf, their parents are not deaf and I doubt they know anyone who is deaf but they have developed a unique means of communication. Their mother admitted to me, "It drives me mad. I've told them it's rude, like whispering but they still do it. We tried to stop it but that just made it worse." 
They might grow out of it or, more likely, they will learn not to use it in front of other people. I have seen adult twins communicate in their own unique ways.
I can't imagine being a twin. I've tried. I can't imagine being so close to an identical twin that there is some sort of unique language between us, that we seem to know what the other is thinking.
Yes, "seeing double" fascinates me.