With reference to some specific exemples in the novel,I would like to know wether the murder of Papa Eugene has liberated and made his family happy.

Mama withstands the abuse because she believes it is just. Ultimately, she poisons Papa because she can see no other way out. The abuse has repressed her to the point that she must resort to murder to escape. Mama is finally liberated from father's tyranny but there is a hefty price. Jaja takes the blame for the murder and is put in prison. Even though Jaja willingly does this as his ultimate act of rebellion, Mama must also live with the guilt. There is also guilt for killing Papa but I think the liberation of not being constantly beaten and humiliated outweighs anything else.