Now that we have a direction to look in to help Mr M we have been able to experiment with ideas other people have found helpful.
M is a sensory seeker - he enjoys rocking, fiddling and chewing things. Usually the need to move is directly proportionate to the excitement and concentration of the moment - the more excited he is the more he needs to move, the more he concentrates the more he chews and rocks.
At the moment Uncle N is staying, so M is pretty excited. I like N's visits because they are long enough at 4 or 5 days for things to calm down and the excitement levels to reduce a fair bit. There is also a lot of playing of games - meaning a lot of sitting and concentrating.
Yesterday we played Small World - a fun strategy game where you try to conquer as many territories as you can with your fantasy race, before the race "goes into decline" and you start again with another. There is a lot of strategy involved - and a fair dose of sibling rivalry between L and M. With five players each round took a while, but the game is limited to eight turns, so it was quite manageable.
M couldn't sit still, but it was a perfect time for him to use his (relatively) new balance cushion*. We have previously spent most meals with my husband or I telling M to stop rocking his chair, "all four feet on the floor please" on endless loop, but since we got the cushion that has almost completely stopped. He still fidgets and jiggles, but the cushion is partly inflated, so whilst he moves the chair does not. It seems to be working well :)
We also noticed that he tends to chew things - toys, remotes, pens, clothes. So we picked up a Chewie Gem * The one we got is slightly different to the linked one, it's too big really to take out, but M has it on a ribbon around his neck and he finds it soothing and relaxing to use.
The third part of our trying things out was a fiddle toy - we bought one that was a stretchy octopus sort of thing. M loved it, it helped him focus, but it didn't last. He pulled and squished it a bit too much and now it is deflated and missing some bobbly bits. That was a bit of an issue because M believes everything has a soul (he has said so many times to me) and a personality, so it was like loosing a friend. We bought him a wooden ball with nobbles on, but it's not quite the same.
The last part of our success with "things" is probably the biggest and best bit. Earlier this year M began to have night terrors - we'd have 30 - 45 minutes of screaming, shouting and swearing every night. Often twice a night. He'd pace around the house and get aggressive if we spoke to him or made physical contact. This happened *every night* for about 4 months. We looked for solutions online - we tried limiting media, talking things through, providing positive endings, disturbing him when it was about the time the terrors normally started. Nothing worked. Then I read about "deep pressure therapy" - M likes to be well wrapped, so I thought we'd give it a go. Then I looked online for weighted blankets, and the cheapest I found was £100! At this point everything else we had tried had failed, I had no more confidence in the blanket than any other thing we had tried, so I was unwilling to try and find that £100. Instead I made one. A £7 sheet (M chose the colour and texture) and £11 worth of "poly pellets". £18 + a bit of time seemed much more reasonable an investment. I had underestimated the time it took to make - I followed this tutorial, which is a nice simple one - but it took me SEVEN HOURS!
After all that time I was wishing I'd just coughed up the £100 . . . but from the first night it worked. Amazingly M sleeps through about 95% of the time now. When he does wake it takes a couple of minutes to soothe him - and he is far less agitated and aggressive. It has been an amazing change, there is so much less tension here because we are all getting a lot more sleep!
Being able to try these things has helped us all. Not everything works for every child, but we have had far more success than I expected, and life is calming down because of that.
* We have used Cheapdisabilityaids.co.uk, and had excellent service from them, however I know other people have had issues with them. This link is just to show you what I mean by the items, not a recommendation of the company :)