What Causes Clay Colored Bowel In Child?

Hi, may I answer your health queries right now ? Please type your query here...           hello sir,i m a doctor recenty passed out...my cousin{F,one & half yr old}is having black stool for tow month..for last 2 days she is having clay coloured stool mixed with black tarry stool....there is no alteration of bowel habit..she is playful,developmental milestones are as per age..they r resing in canada,so i cant tell about her physical findings..she was a lbw premature baby..sir i would b highly obliged if u tell me what may b the possible causes of this condition & what steps need to b taken??good night