I think it depends on your area.
I started the ball rolling in June this year, we went to see the adoption team and a lady came to our house for a visit. Were are still in the 1st stage to be honest.
We were given a booklet of questions to answerer, such as things from our child hood, how we thought about our bringing up, what things are important in our life (maybe religion, friends/family). This just builds up a picture about you and your partner. Then we had to attend a four day course, which I have to say really opened our eyes. It was very interesting and you will learn quite a lot.
You also have a CRB check and a medical from your doctor.
I think stage two is when we have a social worker assigned to us, and they will build a report on us as a couple and individuals, they will speak to our referees and anyone that maybe looking after the child, such as your mum etc.
I hope this helps, but like I said, I think it depends on which area you are from as each will do things differently.
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