Just a passing thought: is the diaper a disposable, of the ultra-thin variety? and could the grit be from the diaper (the super absorbant agent that later feels like jelly beads when saturated), getting mixed with the stool and just not swelling/responding because there is not enough fluid to cause the swelling/softening? I've seen this sand-like grit clinging to the interior surface of off-brand disposable diapers. Again, just a thought. Jeanine Klaus, MS, IBCLC Oakville, Ontario