There were behaviours that stood out. Jack made a lot of high-pitched noises and would run about flapping his arms as if to try to fly.
"He had various other little visual ticks and things that were his way of releasing stress or reacting to visual stimulation. If you were standing in a crowded room he would start reacting," Mr Bothwell recalls.
He also knew that, in the first three years, children develop at different rates, and can also catch up quickly. But when, at age three, Jack could speak only 20 words, they attempted to get a diagnosis.
Mr Bothwell had long thought his son might have an autism spectrum disorder, but it still took around 18 months to get that diagnosis. This is a problem he shares with many parents of children with learning disability.
Perhaps out of fear of labelling, but also because in fact some children do naturally have a development spurt later than others, there tends to be little push for early diagnosis. Jack finally got a name for his problems in November 2011, when he was four.
This delay, says Mr Bothwell, was "quite frightening, because a lot of doctors say that the earlier the interventions are put in place, the better the outcomes for the individual". We waited for a third of his life - that's significant."
Resources are one of the main reasons Mr Bothwell believes diagnosis takes so long. "It takes a whole team to do the diagnosis, and to get them together when they're extremely busy is a real challenge. There's also still a very small resource pool."
Around the time that Jack was diagnosed, Mr Bothwell started to volunteer with Enable Scotland, helping to provide information for other families "who are finding their way in what is a very busy, complicated world". After all, he had seen how bewildering it could be. Though, he and his wife had been highly well-informed - she, a healthcare professional, thoroughly researched from early on what might be happening with Jack - they had seen how slow and difficult the path to diagnosis could be, and also, felt the absence of concrete help in the vacuum immediately after.
Enable - the charity supported by this year's Herald Christmas Appeal - helps and campaigns for children and adults with learning disabilities, assisting them to integrate with their community.
"There wasn't much help available at all," Mr Bothwell recalls. "Here's your diagnosis and a couple of phone numbers to ring. On you go."
As part of the Young Families Committee with Enable, he has been working on a guide so people know what's available, when to ask for it, what are the right agencies and charities to turn to.
"It's the charity sector that actually then steps in and fills the gaps."
Some people feel grief at an autism diagnosis, but that was not what Mr Bothwell felt. He had been behaving as if Jack were autistic for some time. "I think for us it was a relief.because all the warning signs and all the indicators were there and we were treating Jack as if he had autism, and we were putting strategies in our family in place to deal with that."
Bothwell's pleasure and joy in his son is self-evident. "He's an amazing wee guy," he says, "and the way he copes with what to him is a crazy world is quite amazing, and astounding." Jack, he notes, has spikes and troughs in his behaviour. "On a good day," Bothwell adds, "you would not know there was anything different about him. It's only when you try and engage him in conversation you might get a slightly odd conservation, or if he starts to get stressed and into sensory overload, his physical behaviours might start to manifest."
Jack is now six, in Primary 2, and spends part of his week in a mainstream school and the rest in a special educational needs school.
With some skills, like reading, he is ahead for his age; but there are still aspects of life he finds difficult. "We've struggled and we've seen him struggle," Mr Bothwell says.
"I do question if we had the diagnosis earlier, more pre-school support, would Jack actually be doing better just now? We'd like to think he probably would, but there's no way of actually telling."
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