The dog represents an emotional aspect of yourself which usually pertains to feelings of friendship and loyalty. The dog poop would indicate that there is some complaint coming of your feeling of friendship and loyalty. In other words, emotionally you may be inclined “to make a big stink” from the perspective of friendship and loyalty.

Poop in the guest bathroom used by your son, implies that there is some complaint pertaining to a very personal point of view being used by your son. As this is the guest bathroom, there may be an issue related to the idea of guests.

The poop in a room used by your daughter, implies there is also some compliant pertaining to a point of view used by your daughter. In this case the complaint may not appear to be “up front” or legitimate in relation to a position or attitude she might rest very comfortably at ease with. (poop behind the sofa) [Could this relate to her leaving you with all her stuff, including a dog? Would you feel less friendly or somewhat disloyal about complaining?]

The fact that the poop is seemingly hidden would suggest that this complaint has not been made obvious or exposed. In reality you are seeing this complaint to be in relation to your own personal point of view. (dog tend to poop in your bathroom) In other words the complaints are not being directed where they should be – towards son and daughter.