Be available to do whatever is needed, including just listen. Being avoided by others only adds to a grieving parent's pain.
Tell parents you are sorry about what happened to their child and about their pain, but don't say you know how they feel. Only other parents who have had a child die really know what that is like.
Let parents grieve in their own way and at their own pace. It is not helpful to tell them what they should feel or do.
Encourage parents to be patient with themselves and not to expect too much. This is not the time for "shoulds" or "ought to's."
Don't try to fix parents' pain. Reminding them that they still have other children or that they can have another child suggests the child who died is replaceable and not unique.
Use the child's name and share your special memories of the child with his or her parents. Allow them to talk about their child as much and as often as they want to. They may cry but they also will tell you that it makes them happy to talk about their child.
Remember birthdays, anniversaries and other special days. Grieving parents want to know their child has not been forgotten.
Give special attention to the child's brothers and sisters, not only immediately following the death, but also in the months to come. They also are grieving and need support and understanding.