My older 2 have asd so not sure what's "normal" . Ds3 is 12y 8m and has recently started showing signs of puberty. In a lot of ways he seems very young and in others he seems very grown up. He still likes soft play and dressing up but he is also very interested in girls and clearly has a lot of raging hormones. He's still very short, his 9 year old brother and 9 year old cousin are both taller than him (although not by much) and he is still wearing aged 10-11 clothes. I'm thinking his behaviour/development is fairly normal for his age but BIL and SIL are always really shocked at his behaviour. I keep reminding them that although he is shorter than DN, he is in fact 3 years older and has been at secondary school for a year which makes a big difference at their age.
I have of course respected BIL and SIL's request that DS3 doesn't mention farting jokes or any 12a film that he has watched in front of DN but they are shocked that we let him watch some 12a films and things like Michael McIntyre 's big show etc.