I am almost certain that 5.4 yo DD1 has aspergers, but only at a mild level. Toileting (wee and poo, but not as severe as it was even 6 months agao as she can now go two days or more with no accidents) issues, rigid thinking (well, rigid in her way, but she comes out with amazing observations because she thinks everything through :) ) dislike of change, social problems - mostly comes across as being bossy/rude and kind of morbid, but those who know her know she is just trying her best, very advanced at reading but still can't dress and undress herself, tantrums at things like a van not being where it usually is on the school run, etc.
That all sounds a lot more severe than it is, tbh. Most people remark on how she is is unusual, she gets called a bit of a goth or a budding scientist, or say that she is a natural smiths fan :) But that is as far as it goes. I give her little scripts for talking to people, I hold her hand and reassure her, but still encourage her to do things that make her feel funny and I have explained in great detail, with books and videos, why her little sister (2yo) can't read, and why some people believe in God and others don't, and why people don't like being told that they will die soon just because they happen to be over 90, and why not everyone knows that a shooting star is really a meteor and anyway shooting star is a nickname for a meteor and is fine to use, and that it is ok to sometimes slightly break the rules that are written on a bus or food packet or whatever. Sigh.
Overall, though, she is fairly happy as far as I can tell. School have mentioned that she is a bit of a loner and that she will spend all day on a simple task so she gets it 100% right, but they are trying to involve her in stuff more (she does the task that they set as an icebreaker, seems to enjoy it, then wanders off again) and to encourage her to do more than read in a corner or swing on the climbing frame.
DH is just as bad as her and is no help, because he just thinks that she is really cool and that "everyone else is a dick anyway so I don't care if they don't get her" I should add that DH is banned from half the internet for "just telling the truth", and is a quiz champion that almost completely refuses to talk on the phone, and hates all art apart from prose, because in prose they say what they mean instead of making you guess, so he has enough going on there anyway.
At what point would you start to ask for some kind of diagnosis, or is there no need if the child is fairly happy?