Interesting topic. Morning defecation is a habit - and a very good one too. But yes, somtimes the timing is hard to control. There are days when even before I fully awake, I already feel stomach ache damn bad and have to get up and run to the washroom.
Try not to eat too much oily food. Having good fibre intake also help in bowel regularity. Your bowels should be smooth, solid and contiguous. The colour of stool should be either mocha, carob, hickory, pecan, walnut, chocolate, umber or brunette. Cheers!