That question goes back to the beginning of mankind's' time on earth.
The answer is yes! They are there and can help you out if it is aloud for them to do 'this or that' as long as they crossed over and are spiritually sound once they transgressed to the other side.
Human's since the being of time were calling upon the spirits of the dead for help, for guidance. What better way to get help than to ask a loved one! You know what I mean don't you?!
If you were meant to go through a certain amount of crap in your life for learning purposes than maybe they can ease the pain by helping slow down something before it gets out of hand or what have you; but they cannot totally transform things.
We all have a blueprint of our lives and certain things will occur like it or lump it. Just remember one important thing: When you die you walk out of your body. Go to the light, cross over and go back home to where you came from. Don't be a fool and stay in the dark of the past. Be free and enjoy your soul. That is ...when that time comes.
Don't forget you have spirit guides, angels, and the power of God that is within you and that is within all living things that practice being love centered in the heart chakra, and being in harmony with their true self.
:)Know that you are a spirit being having a human experience for your soul's purpose. Connect to your higher self. READ and read some more on the subject. Here's a step in the right direction: http://hubpages.com/religion-philosophy/Reflection...