Hello,
Thanks for posting your query.
In infants the vertebral column in still developing and can be felt as small bumps throughout the central axis of the back . Out of which few vertebrae are more prominent like that between the neck and start of back and in the region between chest and lower back . These are usually hard , bony to feel and the skin overlying is absolutely normal .
In contrast if there is any spinal deformity , following may be observed.
1. A dimple in the skin overlying the spine.
2. A tuft of hair at the end of the spine.
3. A soft enlarging protrusion in the spinal region unlike the small hard vertebrae like feeling.
4. A gap or wide defect in the width of the spine which may show visible indentation
5. Any discrepancy in the development of the two halves of the shoulder or back muscles or limbs.
6. Any other associated anomaly of genital region or ribs or defect in palate etc
7. Any delayed milestones or neurological abnormality like weakness of limbs etc.

Most probably your child doesnot have any of the above features and what you seem to feel is the normal vertebral protruberance .
However if in doubt it's best to get your child examined by your doctor during the routine visit for vaccination or well baby check ups.
Also if you have had a ultrasound during your pregnancy ( anomaly scan during 5 th month or so) it usually determines any spinal defect or abnormality.
Assuming you have a normal antenatal ultrasound of the fetus there is mostly no spinal problem in your baby.
Hope I have answered your query.
I'll be available for any follow up queries.
Kindly accept my answer if you have no further queries.
Regards

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