Everyone has Gemini SOMEWHERE in their personal unique astrological birthchart.
And when you look at someone's parenting style, you do not use their Sun Sign (that is the planet whose location you find using just the month-day of birth).
You have to do up the birthchart (sky map) for the MOMENT that person was born, as seen from where they were born ... and you look at the 5th House in their birthchart. The Sign on the 5th, the planet that rules the 5th, and any planets in the 5th.
If you are going to use astrology, understand that no two people are astrologically identical, so you are only scamming yourself using the stereotypes of the Sun Sign.
I recommend that you start learning what astrology actually IS .. it is NOT Sun Sign astrology.
As for Narcissistic Personality Disorders, those are most often seen when someone has many planets IN Leo and those planets are negatively aspected to other planets in their birthchart. OR if their Sun (in any Sign) is badly-aspected to other planets. Their self-esteem (Sun) is damaged, and they try to pretend they are superior so they don't have to face their fear that they are the opposite.