the technical criteria is 'needs more care/supervision than a another child the same age' (or somethng)
I don't claim DLA. but I do know that planning, shopping, cooking and sorting out dd1's dietary issues (gut issues due ot ASD. can't have dairy, gluten, anythig artificial - colours, flavourings, presevatives etc) takes as much time and energy as sorting out her statement has, or her behavioural issues etc.
the impact on the family is huge - even when we can work up to a day out/holiday (and to be fair, we do ok with these sort of things) the extra impact on planning - where to eat, if we can, taking stuff with us, what could that be etc is huge. really not to be underestimated.
and then, even when you are on an even keel, and up to speed with spending a couple of hours each day doing basic bakery/cooking and shopping, some bugger of a shop discontinues the one thign you need, and it take several hours of research to find somewhere else you can buy it, or a substitute product. it still rules my life, more than her ASD does, now that her school etc is sorted.
all that said, I don't know whether you'd get DLA if you claimed. as it entirely depends on the person reading the form, and whether they think that your reasons for why your child's needs take up so much time/effort are actually valid. and if they don't have an ounce of compassion or imagination, then you are stuffed, tbh.