Here's what consumers have asked with answers from FamilyTime staff and previous consumers.
No, they can't on android. And you can prevent your child from deleting the child app on iOS.
According to my case, customer is the best so far and had answered my all questions very quickly and the agent was informative.
It's even worse than ScreenTime app, I would suggest you to use built in parental controls and avoid using third party apps as these take so much of personal data.