My opinion based on the traditional Indian culture and beliefs/very ancient Chinese beliefs:
Our eyes can only see what comes under it’s visible spectrum while there are cosmic bodies which can’t be seen and technology is far behind to relate to identify them through some lab based instruments. The special quality of humans called feelings reveals their presence hence such beliefs passed down to us, but in cities it’s difficult to realize what’s been spoken about when informed of it.

**Pitru/ Pitra Meaning**

"Pitra"(Mane) is referred to our ancestors or family members who are dead. Pitra’s ethereal body are between God and us. If we have Pitra at our home and we are not worshiping them then we cannot make God happy but if we make Pitra happy then it is not hard to make God happy. ***Pitra are as great as and equivalent to God. ***Pitra are very powerful and believe in give and take rule. If the Pitra are happy then there would be no problem in life but if they are not happy then life is full of issues and problems. This is applicable only in the case if Pitra in a family exists. It is not necessary that every family have Pitra. Pitra is a milestone and God is the ultimate destination. Before the starting of any "Shubh Karya" or assignment it is necessary to worship them. In case if they are not worshiped or provided with the stuff which is dedicated to God then that work will never be successful. It has been seen in many cases that "Pitra" enter in body of some of the family member and show their anger by saying in local language "Mane Tal Diyo" which simply means you ignored me. Later on after apology and worshiping they bless and then the work starts.

There are many myths about Pitra and many people don't even know about Pitra. Coming to the point now **all those family member who die unexpectedly i.e. in accident, disease or die with some wish unfulfilled become Pitra-again it is not necessary that all become Pitra but most of them surely are**. Pitra is a "Yoni" and they are between Human and God or in other words we can say that they are the mediators. Every family has its own Pitra and only those family members can worship them for fruitful results. After death if the dead one goes in Pitra Yoni that means he needs to be worshiped for lifetime. Pitra never goes in heaven or hell they have their own category and they are associated with their family till the dynasty exists. There are many cases in which people die unexpectedly but they don't become Pitra, this is because they don't want any kind of support from their family after death and dissolve them self in God.

Coming to the prakriti or say type of Pitra’s: **We use genetically whatever ancestral belongings, relations, etc(even our body is a gift by them) they left us with therefore we bind ourselves with whatever obligations, attachments too they left us with and expects gratefulness- like remember them on their death tithi day, donate something in their names, feed hungry crows, cows, dogs as they better communicate with passed one’s than humans and will thank them for your doings.**

A family has any of the below 2 types of "Pitra::

**A)Shant Pitra**: These are those who become Pitra after death but are out of the human issues. They believe in God and doesn't mind if they are worshiped or not. If a family has this kind of Pitra then it is not necessary for them to worship. These Pitra are happy in both the cases if treated with respect or not. They don't have any connection with their family members in this case. God is the final judge of the family. God has the direct powers to work for that person. These Pitra are involved into "Bhajans" and "Satsang" and after staying some time in "Pitra Yoni" they progress towards betterment to "Amar Lok Dham" which is bigger heavens where they meet other saints and stay in peace there.

**B)Ashant Pitra**: These are those who are dead but are still stuck with their family emotionally. They want the same respect and care as the other family members get. They are very angry by nature, although they don't harm the family very much but yes problems like money, disease or illness keeps on coming. They want their food and respect on time. They are very effective in giving results and once happy can get you fastest results. Even impossible work for them is not hard. They can change the luck even.
Main things to always remember for any family regarding their Pitra -
A)Pitra are the key to family success.

B)Pitra are essential part of family even after death.

C)Pitra can save us from many unexpected issues.

D)Pitra make environment positive and energetic.

E)Pitra makes work successful.

F)Pitra helps in getting success.

G)Pitra provides peace and prosperity.

If Pitra's are the ancestor's then **why they create problems for their off springs after death or why “Pitra dosh”?:**

This question is very common and most of the people ask that if Pitra are our family members and were loved by us and vice versa then why after death they create problems in life of their living family members? The answer to this is that every one on this earth wants respect and timely food.If these two things are there then a person becomes happy and work more efficiently.Same is applicable with Pitra also. As "Pitra" is a "Yoni" or temperory state of existence just like we people are in "Manuyshya Yoni", the way we deserve respect and food on time the same way Pitra also want the same things from their family members. Although they are not alive but they want their stuff well on time. They live the same way we live but the only difference is the place. Possessing mass we live on earth due to gravity and they in "Pitra Lok" due to they possessing ethereal bodies. If they are happy then family will be surely happy.

**Types of Pitra Dosha**
First one is the dosh that occurs when the departed souls curse their own family because they have not done their yearly ancestral duties wholeheartedly. Some basic requirements were not fulfilled.
Second is the dosh that occurs when an outsider for unforgivable wrongdoings curses the ancestors and the curse continues in the family
The third is when you cannot take care of the old members of your family and leave them on their own without giving them food and water.

**Pitra Dosha symptoms:**
1) There will be lungs and nerve injury whenever a member of the family gets into an accident.
2) Joblessness in the family
3) Existence of long term disease in the family
4) Repeated miscarriages in the family
5) Teeth and gums of children are weak
6) There would be an incessant delay in marriages
7) Some grievous health or mental issue in the child
8) Breaking of relationships
9) Poverty would always create problems in the family
10) Even amenities for a basic living would be scarce
11) Restlessness, confrontations, and disagreements would be a regular scene in the family
12) Family members would get nightmares of say snakes, cockroach, lizard, etc but they need to understand their Pitra giving some indication of presence in medium of dreams.

**Pitra Dosha Standard Remedies:**
If there are many ill effects of the curse of ancestors, there are also ways to correct these faults. The best remedy is to **offer food and water to brahmins during the period of 15 days of Shradh**. During this time, the souls of our ancestors are free to visit the Shradh ceremonies being performed by their children. Besides, brahmins should also be fed on the death anniversary of the departed soul. On these days, most preferably family members should try to prepare a meal that was coveted by the departed soul. There are many other remedies to get relief from this dosha. These are:
*1. Food should be offered to the ancestors on the 15 days of Shradh in the month of Pitra Paksha and on Amavayasas.*

*2. Feed balls of rice to cows*

*3. Pray to Ista Deity without fail daily*

*4. Fulfill the desires and complete the incomplete tasks of the ancestors*

*5. Donate ingredients for preparations of a one-time meal and some money to a brahmin on every Amavasya. You can donate items like whole wheat flour, vegetables (except onion and garlic), ghee, sugar, salt, and spices.*

*6. Take out clothes for your ancestors during any important function in the family.*

*7. Always start any function with the blessings of your ancestors and parents.*


**Disadvantage Of Not Worshipping “Pitra”-**

A)Pitra's if not happy will lead to unsuccessful life.

B)Life is not peaceful.

C)Business of Job issues.

D)Family tensions.

E)Small kids are most of times are ill.

F)Lack of money.

G)All new assignments fails. No matter how much a person worship God but if he as Pitra and family doesn't worship then even the God is not in a state to help. This is because God has given the equivalent status to Pitra's.

**Some village based tips to identifying your family "Pitra"**

Many people say that we think we have Pitra but we are not sure enough! and we would like to know them. The solution to this is very simple.

Few ways to identify the Pitra:

A)Read 11th Chapter of "Shrimad Bhagvad Gita" and within 2-3 days the Pitra will give you a show in the dream. Important fact being you also will vividly remember your dream and then you can start worshiping them.

B)Before sleeping wash your hands and legs remember God and pray that "Who so ever is my Pitra please come in my dream and make me aware of you as i am unable to recognize you". They may come in any form like cockroach, snake or in any other such eye catching getup. The only problem is that they will not reveal their identity you need to understand them or you can consult some Pandit for more details.

C)This is the most efficient way to know their existence. If you have any work which is in doubt that will happen or not assign to Pitra and mention them that if you really exist then make this work successful and if it happens then i will worship you and will accept your presence in my family. Pitra if there will definitely make the work positive and then you can identify them.

Eastern countries having loads of human birth and deaths have to abide to Pitra rituals as one of their right conduct. 

********************
Some relevant western culture too has few surviving rituals to remember dead or non living passed beings as below:
1)“Samhain, now popularly called Halloween, is celebrated on the night of October 31, as per the Celtic belief that this is when the lines between the living and the dead are blurred, and the dead come visit the living. Homes, mostly in the Western hemisphere, are decorated with spooky symbols and characters - ghosts and ghouls, skeletons, witches and spiders, and hollowed out pumpkins carved into shape like faces, with lamps placed inside. The festival also marks the end of summer and the advent of winter, coldest part of the year also associated with death.”
2) On the second day, Pomona, the Roman Goddess of fruit and trees was propitiated, and the apple became a symbol of these celebrations. It is also All Saints' Day, when tribute is paid to martyrs and saints. Then comes the Church-initiated All Souls' Day on November 2 to propitiate the dead, an add-on to the Celtic Samhain on October 31.