Hi Jo, I haven't got any experience with a brace yet, but I have found a great alternative to use for a high chair. Haven't tried it myself, but saw it on the net, called a Beetle Chair or Go Anywhere Chair (??), and it's made from soft material that slips over the back of a chair and there is a little pouch which holds bub in place. I think that the pouch part unhooks enough to get round a brace or plaster, but just check it out on the net. I think you can buy the Go Anywhere one from Mothers Direct, an online store. Have a look, they may be suitable if your dining chairs are adaptable enough, or perhaps it will also fit over a smaller toddlers chair??
Lucy will have another appointment with the physio next week to talk braces and the time frame to transition into one from her cast. We're about half way through this cast, so almost there assuming all goes well. I'll let you know how it goes.
I hope that all your cherubs are going well
Cheers,
Pip.