Prof Eastman explained folie a deux depended on one person being the primary individual, in this case Eileen Pearson, with the other person being in the shadow of them.
The defence say Miss Pearson and her mother suffered from a syndrome called folie a deux which meant the older woman was the dominant figure in the relationship and Miss Pearson therefore had a reduced capacity to appreciate the risk to her mother's health or the conditions they lived in.
As perhaps a definitive word on Iranian intentions and as a suggestion of the dangerous folie de grandeur that marks this particular gang of tyrants, Iranian Foreign Minister Manouchehr Mottaki has recently offered an arrogant and provocative fillip that Iran would continue to enrich uranium even if it were supplied with nuclear fuel for energy generation.