^^ brother thanks for bringing that up.
Hazrat Anas (radi Allahu anhu) asked the Prophet (sallal laahu alaihi wasallam): "If we send Sawaab to the deceased, give Sadaqa and Khayraat and ask Du'a for them, does this reach them?" The Prophet (sallal laahu alaihi wasallam) said: "Verily it reaches them. Read Salaah for them as you read for yourself and fast for them as you fast for yourself. In other words, make Esaale Sawaab of Salaah and Saum for them." The meaning of this Hadith Shareef is that we should send the Sawaab of our actions to the deceased, since in reality one cannot perform Salaah and keep fast for another person or on his behalf, but we can send the Sawaab of our actions to them.
and another one
The Prophet (sallal laahu alaihi wasallam) as said: "When a person passes away and the family of the deceased gives Sadaqa, Khayraat and makes Du'a for him, then Sayyiduna Jibraeel (alaihis salaam) takes it to them in their graves on a tray that is beautifully decorated. When they receive this, they become so pleased as if someone in the world becomes pleased on receiving a gift, and his neighbour who has not received any Sawaab becomes sad".