Distance between nested movieclips

Hi,

Is it possible to find the distance between two nested movieclips just by referencing their parents?

For example, I have two movieclips mc1 and mc2. In mc2, there is another movieclip called mc2child1. Since mc1 and mc2 share the same timeline and mc2 moves away, I can easily find their distance using mc2.x - mc1.x (assuming y is the same, so I skip the pythagoras theorem here for simplicity).

What if the animation is done on different timeline? Let’s say mc2child1 moves away. When compiled, the stage shows mc2 moving away from mc1. From this, how am I to find their distance?

By “right”, I will need to use mc2.mc2child1.x and convert it to global coordinates and calculate from there. But, what if I don’t have a reference to the child of mc2? Can I use mc2 itself to check the distance as this way, mc2 does not change its x position but instead its child does.

It might be confusing so I have included a fla showing the different situations.