According to Brihatparashara there are total 14 kinds of Shapit Yoga Pitra dosha is one of them. In Vedic astrology Pitru dosha is said to be most dangerous dosha, and considered to be a curse form the ancestors. In practical way I do not think any body’s ancestors can curse their own future generations, we can say Pitra dosha is a result of karmic debts of the ancestors and the native has to pay it.Some also says usually when the native has not performed the last rites for his forefathers in his previous life and failed to liberate them from the ghostly existence then this dosha is to be happened in one’s horoscope. It means that the ancestors of such native are themselves cursed; hence the native has to engage in more good karmas so that his ancestors as well as he may get rid of the sufferings caused by such Pitra dosha.Native can do Pitra tarpan or shraadh in the Ashwin Krishna paksha to get relief from its effects.
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