They are most likely new cavities forming. Ideally, best to consult a pediatric dentist for further care and treatment if required. If you're unable to visit a dentist right away, please continue brushing twice a day with a small amount of kids toothpaste and control
sugar intake. If child is still being breast fed or bottle fed before sleeping, try to slowly discontinue the feeding habit.
Next Steps
visit pediatric dentist
Health Tips
brushing and diet control