Well, relax , , your boyfriend is not suffering from any multiple personality disorder if that is what is bothering you, he is just having 2 parasomnias ( sleep disorders), namely , Somnambulism ( sleep walking) and Somniloquy ( sleep talking ), and these are no where as serious as MULTIPLE PERSONALITY DISORDER / SPLIT PERSONALITY DISORDER .
You see, such parasomnias can occur together , as you are well aware that your boyfriend used to sleep walk , and presently he does sleep talk , and such parasomnias are often triggered by Stressful conditions or situations, since you have been having a sort of tiff with him lately , this might have stressed him out and triggered the Sleep taliking incident where in he talked in a child's voice , which by your admission occurred at 2 am , when he is usually asleep . You see, to label a person as having muliple personality , first of all , the person should not be asleep , and should be fully conscious , and secondly , such kind of behaviour should have been consistent throughout the day and night , and should not be time bound as in occurring only at night , when the person is usually in sleep.
So, do not worry ,as it is a case of 2 parasomnias , which are not that serious , often people / their partners / family members avoid such sleep talking / sleep walking episodes for years together.
However , in order to confirm the diagnosis of Parasomnias , somnambulism and somniloquy , you may get a Polysomnography test, done on him , which is an investigation for detecting parasomnias. From this investigation , you will have a definitive evidence of his parasomnia condition, which is actually quite common.
As far as treatment is concerned for such parasomnias , i suggest you ask his family doctor to start him on a benzodiazepine such as Klonopin ( clonazepam ) , 0.5 mg , at night before sleep , ( make sure you shall discuss the dose with the doctor), and continue this drug for 4-6 weeks , and then slowly stop it completely.
I am mentioning below a few links which wil throw more light on parasomnias , sleep talking , sleep walking.
So, i suggest do not draw any hasty conclusions , it is just a case of parasomnias , which can be easliy confirmed by Polsomnography test , and can be treated by using a benzodiazepine , and more so , it is not that a serious condition , except the fact that it may annoy the family members once a while or the sleep walker may hurt himself .
I wish you and your boyfriend all the best. Do not worry , and take care...
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