parent to a linked object

hey, for my latest game, i have created a boat, which is for now my player, in one blend file, and made a river in another blend file, and lined the boat in. my question is this: how can i slow parent a camera to the boat, i have tried lots of different things, but nothing seems to work.

thanks in advance

slow-parent the camera in the original .blend file. then add them both to a group (maybe you have already done that?) and link in the group, rather than the object.

or

Slow parent an empty to the boat in the linked file.
At game startup dynamicall parent the camera to the empty with python [with setParent()]. The empty should be easy to find as long there is no other one with the same name.