How can i protect my house of evil spirits..?

so this might sound crazy but i recently have a big suspices my mothere in law does witch craft n all that stuff its a really long story n i have a 2 year old n me n my sister in law feel like wen she comes to visit she has evil spirits fallowing her n lives them at r house we have experience some stuff that has gave us that thought n my worry is my son we know she wishes the worse for us because she do sent like us its a beyond long story but all i want to know is how can i protect my house n my self n son from her evil ness n evil spirits plz help ... if u have nothing nice n good to say plz dnt comment...