In 1868 he gave an account of 13 other affected children.
No one knows just how many affected children are born each year.
In some cases, parents of affected children raised the research money themselves.
Social service workers will begin interviewing parents of the affected children next month.
These three affected children died at ages of 14, 2 and 3 months respectively.
The brain is large and malformed in all affected children.
In some affected children, the eye(s) may become red and/or painful.
But even if only a small percentage of affected children were missed, it would have serious potential consequences.
Affected children usually show the first signs of difficulty walking aged one to three.
The affected children face permanent disabilities in certain areas and require long term care.