I wanted to add, when I adopted, attachment disorder was the new explanation for everything. Therapists from the States would come over and we adopters would go along, then try to get professionals to take us seriously. Some professionals were terribly excited about it. My girls got seen at the Post Adoption Centre when they were 4 and 5 and they were given attachment based diagnoses.
But I was never convinced and the years brought new diagnoses. And other adopters found the same. By the time our kids were in their teens, adhd and asd were more commonly being diagnosed.and genetic deletions. Then FASD.
Anyway, the feeling back in the day was that if you fixed the attachment, the other problems would fall away.
My elder daughter had a Statement (later ehc plan) for emotional behavioural difficulties which she got in Reception. Everyone at school was convinced she was bright enough (the ed psych had scored her on the 66% percentile). I wasn't convinced.
I contacted Family Futures in london and asked if I could use their ed psych privately. He was incredibly eminent- he had been president of the college of Ed psychs but was now retired and helping FF, seeing some of the most challenging children in the adoption system. So I reckoned he was perfect.
He ran all the tests then called me in and told me my daughter had a learning disability. IQ of 56, which put her in the bottom 1%. He said "I'm not picking up attachment disorder at all, she is delightful".
So, we changed tack completely. Got her Statement changed to mld and she went to a mld school.
Later she was assessed by the genetics clinic due to a medical condition. She was found to have a deletion on one gene which is connected to learning disabilities. Her sister has the same genetic deletion but isn't affected in the same way. Apparently boys with it are more badly affected. They were both assessed there for FASD but we were told it was unlikely.
Later on she was diagnosed with autism at CAMHS by a psychologist- we were having another go at therapy due to her jealousy over her sister. And the therapy made no difference whatsoever, which is one of the reasons the psychologist diagnosed asd.
Years earlier she had been diagnosed with adhd at CAMHS by a psychiatrist.
My other daughter has a similar tale of various diagnoses.
So what I'm saying is, you can get multiple diagnoses over the years depending on who you see and their expertise and area of interest, flavour of the month etc.
You can only do what you can. Personally I would ask for a genetics assessment, a FASD assessment and an asd assessment. Also ask school for a speech and language assessment if possible. And keep an open mind about any diagnoses you get.