I hope you will forgive my writing so directly. You are asking very direct and searching questions, which I believe, deserve honest answers.
First of all, I don?t think you are selfish at all ? I think we all become parent for selfish reasons ? adopters are no different! I also think its just fine to want a sibling for your DD. I guess you know that SS will expect you to have finished any assisted conception treatment that you plan to have? You don?t have to have had trementn for infertility - its fine to decide not to do that if that?s what you want. Its just SS will discuss this with you in some detail and will want confirmation from your GP.
You sound as if you know quite a lot about attachment issues and I think you are right - some children are simply so troubled that they need a therapeutic environment. I guess if you are thinking of caring for a child with RAD you need to be realistic about the resources you might need. E.g. one of you at home full time, appropriate specialist educational and psychological services nearby, excellent post placement support
I think you would also have to accept that you will never be ?normal? family again, in that you will be a family affected by a disability, albeit a psychological / behavioural / psychiatric one. Its one thing to work with damaged children 40 hours a week, with every weekend of and 35 days holiday a year. It?s to care for one 168 hours a week with 10 days respite a year.
I guess the biggest consideration is how adopting a troubled child will affect your DD?s life. So, for example, if your new child cant cope with family holidays or days out, there will be implication for your her Do you have family members who could care for your Dd while you remain at home with your other child? How would you feel about this? If your new child is excluded from school, will your Dd cope?
?I do often feel stuck in my job in that to make a real difference to a child?s life you need to be able to stick with them; they need soemone/somepoeple that won't give up, and no paid position will grant that role.?
I appreciate that you want to make a positive difference in a child?s life. But please be aware that children with RAD will form superficial attachments very quickly with therapists/ workers and not all or with great difficulty with parent figures, especially mothers. Parenting such a child will not be the same kind of relationship, only deeper and longer term. These children CAN relate to workers for the very reason that are superficial / short term/ only do it because they are paid/ not parents figures. That?s why traditional psychotherapy etc doesn?t work for them.
?We are a happy family and we function well, there feels like there is a lot of good stuff to goaround, we have more than we need if that makes sense. Sometimes I worry that too much good stuff will go bad if there arn't anymore children.?
I understand that motivation; of feeling blessed in some way by the good things you have and motivated to share that with another child. It?s a very common feeling in prospective adopters ? they are mostly good people . I think it can be hard to accept that what you consider to be ?good ? things are often not seen the same way by a child. It can feel very different and threatening and they can put a lot of energy into changing things to make them more familiar. So if they are used to chaos, lack of routine, not attending school, arguing, adults fighting, police and social workers around etc they will seek to re create that in your home
I suspect that you are prepared to adopt a troubled and disturbed child, who has known loss, neglect, chaos and abuse. You are hoping that when you take them into your loving functional family they will change to be like you. In fact they are hoping (unconsciously of course) that the opposite will occur ? that your family will become like their own.
You said that you are thinking about your reasons for doing this. I am not worried that you will do it for the ? wrong? reasons ? I am worried that your hopes and expectations will not be fulfilled and your family life will be altered in ways that you do not want.
I would not normally be so blunt, but I sense that you are asking searching questions of yourself here and i want to honour that