That's a metaphor - of course you shouldn't treat your reports like children. But if they possess the following attitude, it's on you as the manager to let them know that it's not an acceptable practice on your team.
> they seem to take an attitude that if they hit something they don't already know, it's perfectly reasonable to stop progressing it and just declare they need help
This advice doesn't stand on its own; you'll need both more specific tactics and a broader strategy for dealing with the situation (providing tooling or scaffolding for improving their behavior). But the fact of the matter is that everything else you do for them won't matter if you condone this behavior - which you are, by allowing it to keep happening.
PS I am an engineer-turned-manager and this is easily the least favorite part of the job for me as I get used to it. But it is ultimately your responsibility to do so, and you are impeding your own ability to improve as a manager the longer you resist doing it.