Space at coxis

If your baby was born with medical professionals involved, they would have checked the spine for any deformities. Some infants are born with a indentation (but no actual opening) near the base of the spine and there is usually no cause for alarm. You would need to keep the crevice clean from feces. My daughter, who is a twin, had a divet and we used a lot of diaper wipes to keep the area clean and it eventually went away as she grew. In other cases, an opening which exposes tissue, etc could be a sign of spina bifida, or not a complete development of covering the coccyx and the medical professionals would have notified you and performed additional studies. In any case, you can always check with a physician to ease your mind.