I am sorry for your loss.
Only a handful of states (Iowa, Kentucky, Maryland, Nebraska, New Jersey and Pennsylvania) impose an inheritance tax and most all of them exempt lineal descendants. Further, the estate typically handles any inheritance tax issues.
All assets belonging to your mother will be stepped up to their fair market values as of the date of her passing. If an executor/administrator is handling the estate, you may receive a K-1 (1041) for any post-death appreciation and/or income.
