You would have observed that sometimes real brothers and sisters become the implacable enemy & opponent. It is also said in Mahabharat the great epic that if enemy is your real brother then it is rather impossible to face.
Let us discuss this issue on the astrological point of view. First of all, who is real? Real brother, real sister, Mother, Father and Husband-wife. In astrology, Mars represents brother-sister, Sun for father, Moon for mother, Venus for wife.
The different house of the horoscope also represents different relationship. Seventh house of the kundali represents wife and third house of the kundali brother-sister.
There is house which represents enemy also. Sixth house of the horoscope represents enemy. The lord of the sixth house, the lord of the nakshatra of this house also enemy for native but it does not mean that this principal will be applied everywhere. Other planets may affect this.
It can be decided after fully reading the horoscope that who is real enemy or not.
When the aspect of the lord of sixth house is on Mars then there is lack of love and intimacy between the siblings.
When the aspect of the lord of sixth house is on Moon then the native shall have less affection with his mother. Rahu’s aspect make it more panic and create more gaps in relations.
When the aspect of the lord of sixth house is on Sun then there shall be differences between the native and his father. Their thinking will not match and they both will be of opposite nature.
The siblings of the Native becomes his enemy when the lord of the third house of the horoscope situated in the ninth or tenth house of the horoscope. He should not believe his siblings. He should take extra care when the matter of property, estate, assets.
The siblings of Native leave no chance to cheat him if Rahu sits with the lord of third house.
The siblings of native deceive him during the whole life if the lord of third house of the kundali situated in the sixth house and lord of sixth house of the kundali sits anywhere in the kundali except third and ninth house.