The answer is bladder control usually is achieved before bowel control.
Bowel control usually is achieved before bladder control. The child should not be forced to sit for long periods . The ability to remove clothing is one of the physical signs of readiness for toilet training. The physical ability to control the urethral sphincters is achieved some time after the child is walking, probably between the ages of 18 and 24 months.
You would expect to find elastic fibers