How a multiple creates their own inner families is as individual as each person with multiple personality is themselves. Even though symptoms vary from multiple to multiple, there are some basic consistencies. Here you will find those symptoms which are common to multiples.
Multiples do hear voices, but are merely the personalities within, communicating with one another. Often times, the MPD is misdiagnosed as a schizophrenic due to "hearing voices", but the multiple personality hears the voices inside their head in contrast to the schizophrenic which hears them from outside of themselves. Often a multiple before diagnosis will speak of noise or clatter inside making it difficult for them to concentrate. It is possible for the multiple to hear many distinct and separate voices, of all ages talking at the same time.
Each alter within a multiple has their own history, personalities that are unique to them, body movements, facial expressions, the way they express verbal communication, voice tone and pitch. You might encounter a small child who hides her face and speaks in a childlike voice. Another child within the same system of personalities might be gregarious and charming. The description above would hold true for any age alter and are just two examples of the variance you might find within the same age group of any of the alters.
In diagnosising MPD another indicator is the difference in handwriting styles. Personally, this is something I noticed about myself long before I knew I was a multiple. On any single page of writing, my handwriting style would dramatically change from one paragraph to the next, and sometimes from one word to the next.
Time loss is quite common in the non-conscious multiple. For the non-conscious multiple the time losses can be devestating. Time loss can occur when something triggers an alter that the host is unaware of. The non-conscious multiple might find themselves in a place or talking to someone they don't even know. The length and duration of the time loss depends on how the multiple's system works and if a more dominant personality can remain in control. There is a bit of time loss on occasion even for the co-conscious multiple, but usually amounting to only brief periods.
There are other symptoms that are not strictly indigenous to the multiple such as body memories, nightmares, depression, and self abuse.