If I understand the question correctly, there are many ways to do that..
For example, something like this should work:
give the hitbox a variable ready (original value 0)
for each family
pick by comparison - hitbox.ready = 0
hitbox set position to family.x,family.y
hitbox set value ready = 1
hitbox pin to family
or if you have to create the hitboxes, you don't even need the variable
for each family
create hitbox at x=family.x y = family.y
-- hitbox pin to family