I was just wondering if it's possible to determine the allowed_children of a page type on the fly?

I have a Holder type which I'm using in multiple instances. The only difference between each instance is the children that's allowed per holder, and if its possible I'd like to not have to extend the holder class just to encapsulate this information.

I'm wondering if it's possible to do something like this:

if($this->Title == "Activities"){
$allowed_children = "Activity"
}

if($this->Title == "Events"){
$allowed_children = "Event"
}