Don't work with both object types, just the one. 'selected' is accessible from each object now. You can do this either way: use only Family, or use only each object type:
On tap furniture -> furniture:selected=1
On tap chair -> chair:selected=1
Event 2 is correct.
(I'd suggest using 'On touched object' - 'On tap' is a specific gesture, and doesn't always work as you'd expect, for simple selections).