If there are children in the house remember they are grieving too. Allow them to speak of their loss and cry like everyone else. Never assume that a person isn't grieving just because they are not crying. They are hurting on the inside. Everyone is different.
Some people hold pain inside and grieve in silence.
Never assume when the funeral is over that the grief is over, that person has suffered a loss. It can go on for a long time and sometimes that is when they need you the most. Every person that we loose in our life makes our life different and we have to adjust to the loss. Never say they are in a better place they don't want to hear it, even though sometimes it is true when someone dies of a terrible illness. Some people cannot be religious at this time, some can.