Hey so I am researching sidechains, I see how useful they can be for new coins that want to remain independent but still draw power from an already established network, but one problem I saw is that "Sidechains are responsible for securing their own network". Does this mean that it's impossible for a side chain to use the securing power of it's main chain to secure itself and it's transactions or is there a way around this?

EDIT: I was doing more research and I read more about Ardor, in which I saw that Ardor claims that their child chains ARE secured by the main chain and that those who create child-chains do not have to worry about security. How does that work?