Ladies ladies 
I know a little about controlled trials, y'know.
The Cochrane Review doesn't say that weighted vests are crap.
The Cochrane Review doesn't say that the children are simply pinned down as DBennet suggests. I mean, 5% body weight is not going to act like a concrete block, is it?
The Cochrane Review doesn't say that weighted vests don't help.
What the Cochrane Review does say is that the research was so badly designed, so flaky, so variable in outcome and the data so difficult to specify, that on that basis, they cannot recommend that weighted vests are used clinically as a treatment.
However, that does not say that weighted vests are not useful, do not work, and the OP is lying 
At worst, it can be said that the effects of a weighted vest is anecdotal.
Show me anyone who would refuse a weighted item simply because there is no double blind randomised controlled trial of it, and I will show you someone who doesn't have a child with behavioural and sensory difficulties 