Sisters new family came into our house without my parents permission and moved her out giving my mom ptsd of people being in our house while she’s home alone

Location: Iowa

for some context my sister decided she was going to marry a guy from Indiana, so his parents snuck into our house with my sisters permission unbeknownst to my mom who’s the homeowner and was home alone that morning, she woke up at 9:30am and went out of her room to these people sneaking around our living room moving my sister out, and my mom has had anxiety and ptsd since thinking someone’s in her house at all hours of the night. i think since my sister is a resident of the house they were technically allowed in because she let them in, but is there anything legally we can do against the other family for causing semi long lasting anxiety. they also didn’t leave immediately when my mom yelled at them to get out of our house.