Stig (my daughter/son-in-law's dog) is visiting, and has discovered the cat cubes.
He puts a squeaky ball (or one of his rawhides)
inside a cube and then tries to retrieve it, but this has been happening.
Some of the time he can get himself out (I separated the cubes that had been velcroed together), but other times he seems a little embarrassed and has to come to John or me to get himself rescued.