So I made a start. I put the search terms: " vanishing twin+schizophrenia" into Google Scholar, expecting that some research worker somewhere may have pursued this, even slightly. But no: the only article linking the two was a desperate blog post written by a mother of a schizophrenic son.
When my son was born there were 2 placentas. I have enough signs of 'vanishing twin syndrome' to now put the picture together. He may have been a twin, and by all the signs I suffered and witnessed he probably was. Twins are on my father's side. One in eight of us apparently start off in utero as a twin, and the classic signs of losing a twin are a perceived miscarriage - everything fits and I've ticked all the boxes.
A very very difficult baby/toddler/teen - in a world of his own, but very very intellegent. Teachers found him non complient, wanting to do his own thing, yet the educational psychologist thought him highly mature and bright - aged six. Then aged 17 he decided to misuse substances and had a terrifying psychotic attack, and soon after was labelled schizophrenic.
He's now almost 30 years old, and has been in and out of psychiatric services all of that time. No one is listening - least of all the medics that my son's pregnancy, birth, early years were cause for concern. No, all that has been cut off, and the medics are treating him like he has always been a schizophrenic man with a ''normal'' medical history before that.