ANSWER:

The reward is the same for everyone.  One sacrifice is for the entire family living under one roof and they can include their deceased parents or grandparents in it as well. You cannot include anyone else.

On sacrificing a goat or prescribed animals on Eid ul Adha, we sacrifice to Allah on behalf of one or many person, my question if one sacrifice is given on behalf of many, does the reward is getting splitted as many? If 50 rewards in total means, 5 person get 10 reward each? Or each person gets the whole 50 reward? Please clarify