My daughter was 5yrs before I realised she might have an ASD. She is and always has been very sociable, alert and cheerful and she met all her milestones and was way ahead on some of them. The only thing that I was concerned about when she was very young was her obvious sensory issues (although I didn't recognise it as that, at the time). Some kids don't have any signs at a young age and seem like perfect babies. There's no way of knowing, but try not to worry at all. In all honesty, our daughter's diagnosis has been anything but the end of our dreams. She's a great wee soul and there's no Mum prouder than me.
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"We act as though comfort and luxury were the chief requirements of life, when all we need to make us really happy is something to be enthusiatic about." Charles Kingsley