Mother died stepfather won't let mothers kids have anything. Us selling or trashing items without consent. Do we have any legal rights?

The biological children of a deceased person has rights under Indiana probate code.  There are many different types of ownership, and there indeed may be assets that stepfather legally owns free and clear of any claim by the biological.  However, the children have a right under the law to a certain percentage of the probate estate.    You would be well advised to consult with a probate atty in the county where your mother resided at the time of her death.  There are time limits, so make that attorney appointment ASAP.  Good luck!