Trouble with relative over will-what can we do?

My husband is executor to his mothers estate-there was not much to it,some personal effects and a house.The house was to be sold-the money divided between my husband and his brother.His brother has always been a trouble maker,he has called and threatened us,left haring message(which we have on tape)He called a lawyer to try to sue us-so we had to get a lawyer-all of this because he did not like the fact that my husband was put in charge of the will by his mother.This man is close to 50 years old and acts like a 13 year old.My husband went to mow the gr at the house that we are selling and found where the brother has been taking stuff off of the property-we know it was him because he called our realtor and said he was going to "clean up the property"he has no business even being there.He is also bad mouthing my husband to anyone he talks to -including our realtor-is there anything we can do to make him stop?I told my husband to file a police report stating he is tresping on the property and ask them for advice-should we also call our lawyer about him slandering my husband?We feel like this guy can get away with everything while we have to stand and take it-Help!!