The approval process for becoming a foster carer is so involved and thorough that it's hard to believe that there are can be anything left to know when you finally start doing the job. And yet it seems that while you've told them every conceivable thing about yourself, there's plenty you don't seem to find out about what it really means to care for other people's children.
I could write a long list, but today I'm inclined to concentrate on just one thing: the amount of time you spend around distressed relatives.
At some point during the approval process I gained the distinct impression that, no matter how many contacts the children I cared for would have, I would not have to meet family members if I didn't want to. I'm sure this is true, but in fact I have met not only parents but also stacks of extended family members for both the children I've looked after.
And not just met. I've spent considerable time with some of these people, heard their stories and got to see the world from their point of view.
This last week has been a particularly hard one for the families of both the children in my care. There has been bad news to digest and a need to adjust to new and hard realities. At every contact, there have been tears or brave faces, sometimes recriminations and the searching questions of confused and hurting people.
It is easy to demonise the families of children who end up in care. 'How could anyone harm an innocent child?' is an expression I hear quite frequently, and it's an understandable reaction. But behind every child in care is a family in crisis, people whose situation is completely chaotic, whose lives went out of control a long time ago, and now they don't know how to begin to rebuild.
Some of these mums and dads have their own sad stories of childhoods that were desperate and brutal, of exploitation, violence and abuse. Some were in care themselves, others perhaps should have been. Then there are the heartbroken grandparents who know that one day soon they will have to say goodbye to their beloved grandchild for the last time, and none of it is their fault. Behind the victims, there are often just more victims.
So this week, I have been an observer to all kinds of pain. I have spoken soothing words to a mother whose child reaches out for a stranger rather than for her. I have listened to angry outpourings about social services, other family members and the world in general. I have comforted those who are crying and turned away from tears I was not meant to see.
These are the things they don't tell you.