The psychology may be defined as the field of biology that mainly deals with the study of the mind and behavior of an individual. The psychology includes the different field like patho psychology, social psychology and cultural psychology.
The personality study of the person is also studied in psychology. The personality may be defined as the behavior of an individual that distinguishes it from the other individual. The personality reflects the thinking ability of the individual as well.
If each have 12 including their selves that would be 13. 13 times 2 is 26 -2 is 24 if your including the parter then it would be 25 not including your self