Is my child entitled to her deasesed mothers belongings she is her only living heir, my child is a minor?

If there was a will, the will determines who inherits.
If no will, the laws go by state. You can tell us your state, or Google 'intestate (your state).' If her mother died while married, that will matter in any state.

... or google 'intestate (your state).' ...

That might be confusing for those unfamiliar with the word "intestate". (not to be confused with "interstate") It means "without a will".
Each state, and most other places, have legal rules which determine who (in relation to a decedent) inherits, and what they get, in the absence of a will.

True!