Try Mamaearth natural berry blast kids toothpaste. its made for natural ingredients.

Try mamaearth's toothpaste.
It is very good for babies as it is SLS and fluoride free which does not harm baby.
Try it.

Use mama earth's toothpaste for ur kid it's completely safe ND chemical free

Try to use a less flouride toothpaste.. such as mee mee brand or even colgate kids toothpaste!

Any soft brush with a mild tooth paste will be good, and brushing should be under your strict surveillance.