Is is interesting that they saw with the angels, loved ones who have passed on. Some people think that any appearance of a dead person is demonic. This could not have been a demonic appearance. I know of people and know two people personally who saw someone they loved appear to them and even spoke to them. They did not seek the appearance. We know seeking to converse with the dead is evil and would cause demonic activity. I believe if the appearance is not demonically promoted or even promoted by us then it must be real. In other words it must be God promoted. This happened on the Mount of Transfiguration. There is a biblical example for this in that.