Hello Tmerc:

That's a tough question to answer. First of all, there are some unknown variables, such as what kind of information your friend is open to and what kind of personal experience you have to share that would be helpful.

If I lost a child I would try to see beyond the personal lost factor and consider the welfare of my child.  If I could become certain that the afterlife exists, I would be certain that my child still exists as a conscious being. If I understood that our time in this World is a temporary game we play until we get back to being the kind of beings we truly are, I would know that love and fullfillment isn't dependent on who I am able to relate with while in this World.

On the one hand I have found that it is difficult to get people to feel confident about their immortality if they  lack experience, on the other hand there are near death experiencers who have  found that they can inspire hospice patients to lose their fear. Perhaps hospice patients are more open to considering the existence of the afterlife because their precarious situation makes it so they are more willing to question the beliefs and attachments that interfere with their ability to become certain about the existence of the afterlife.

Perhaps the below site will be useful.  It contains information about people who have made contact with deceased loved ones in various ways.

http://www.after-death.com/

P.S. Some sources say that when a person grieves about a deceased loved one too much, such grievance can make it difficult for a deceased person to move on towards the light.