Showing hidden lines of in-place Families.

Quite often In-place Families families don't show their hidden lines and the show and remove hidden line tools are disabled when the graphics style is set to hidden line.

Strange but true.

If you switch the view discipline from Structural to Architectural then these tools are enabled.

Apply the hidden lines by first clicking the object you want to see through, then the object you want to see under.

Remember to switch your view back to Structural afterwards.