altho the exact cause of autism hasnt been identified, it is known that there is a genetic factor at play. autism often runs in families, having one autistic child increases the odds of having another autistic child, and having an autistic parent increases the odds that a child or children born to that parent will be autistic. so yes, it can be hereditary.
my youngest son's diagnosis was delayed in large part due to us just attributing his autistic traits to inheritance from his father. K talked late, well his dad did, too, so its ok. K didnt smile hardly at all as a baby, well his dad has a serious demeanor also, he just got it from his dad. K didnt answer to his name, didnt play with other kids, showed repetitive motor movements, but hey his dad does all those things so hes just like his dad. well DUH =) thats because his dad is autistic, too. my SO was officially diagnosed with classic autism 9 months after our youngest got his diagnosis.
one often misunderstood trait of autism is a difficulty with showing emotion in the typical manner. often its said autistics dont show emotion, which is very wrong, they just do so in their own way, like so many other things they do. its not uncommon for them to laugh at inappropriate times, my son has this issue and laughs when hes in trouble. its a spontaneous showing of emotion, and not something they can always control. my 5 yr old put it best when he said to me, "sometimes i laugh when i dont want to."
welcome to the wonderful world of autism, rissa =) its a wild ride.
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Neurotypically confused.
partner to: D - 40 yrs med dx classic autism
mother to 3 sons:
K - 6 yrs med/school dx classic autism
C - 8 yrs NT
N - 15 yrs school dx AS