Hi FruitCider, good luck with the process.
Our experience was we had a birth child (DD) and when she was 7, nearly 8, we met a social worker in our home and discussed the possibility of adopting. This was a number of months after attending an open evening with our local adoption authority. Although we had been talking about this for some time, while undergoing fertility treatment (and also having wanted to adopt for a long time!).
The process took us 20 months from that meeting to bringing our three (almost 4) year old son home to live with us.
Our son is quite emotional but aside from that he is currently presenting as a very normal little boy, very loving and affectionate and doing well at school.
I read a lot on here about attachment and how to do things differently. Although, as our dd has dyslexia and autistic tendencies, parenting our dd is not typically standard, certainly between ages 6 and 8 at least!
I think, for me, the key thing is that when there are issues, with anything with ds, my mind immediately goes (rightly, I believe) to adoption and whether losing his birth family, and then his foster family, and his early life may be the cause of the issues.
He has lost a lot. Although we have letterbox contact with the birth family and our son sees his former foster carer about two times a year, our son has lost these relationships. Plus the chaotic life he led before being taken into care has obviously impacted him.
The love I feel for our son is very intense. Sometimes it is expressed slightly different to our dd in that I've known her for almost 12 years and him for only two and a half. Plus their ages are quite diverse, she is almost 12 and he is half that. This big age difference has been helpful, they are at different stages and need different things and when they are both in their 20s the age difference will not seem so large and will not (I feel sure) affect their relationship as adults.
The love I feel for our son includes the fact that I feel a sense of responsibility for him, I would say it is in some ways even stronger than for our dd, because we chose him in such a way, we kind of knew what we were getting into! So I feel I must really do my best for him. BUT of course I feel that I must do that for dd too, so really there is no difference between the love I feel for either of my kids. It is just expressed differently and I think actually their age is the key factor.
I only ever treat ds differently when it is for his benefit, e.g. I am very careful about doing what I have said I will do and being someone he can trust, but again part of that is that dd knows she can trust me (I hope) after almost 12 years!
I am rambling. I hope I am just giving you a snap shot!