🚀 go-pugleaf

I have the following design problem:

I have a package called core that contains classes Entity and Property.
These are meant to be used as superclasses in various other packages. An
Entity can have zero or more Properties declared as its fields.

The problem is that I'd like Property to know the Entity that contains it.
I'd refer to this Entity as parent. I have defined a public method setParent
to Property. Entity should loop through all its Properties and call this
method after the Entity has been created. If I work in the core package this
works ok, but when I want to work in another package (e.g. application),
Entity cannot access the Properties unless I declare them public. Is there
an elegant way to solve this?

Currently I see two alternatives: All Properties need to be public or I need
to give the Entity in Property's constructor as an argument. Are there any
other choises?

Pasi