There are many more plants in your yard that are toxic and some are much more attractive to children. Wild things like pigeon pea, and nightshade even have red berries that look very edible. I'm sure you and your DIL watch those kids closely enough to be sure they would not eat any part of a plant without you giving it to them. Brugs also get tall quickly enough that you could prune it up out of reach of a very small child or a dog.
All my brugs grow well in large containers. Our soil here is too poor and the nematodes kill them off in a year if they do survive that long in the ground. I would definitely take some pains to protect them in winter where you are, though. Place the containers on a south-facing wall or somewhere they would be warm, and mulch around them with leaves or other insulating material.
Or just take cuttings each fall, and start new plants in the springtime. I've kept cuttings in water for so long, they've bloomed! I had to once break a wine bottle to get a rooted cutting out, there were so many roots it wouldn't come out the neck of the bottle.
For now, I'd advise you to keep the cuttings indoors, in water or in small pots until late Feb. or March. A new, small plant isn't going to survive outdoors through winter.
