As much as I hate to say this, you'd do best to not try and contact any of the kids again. Mrs. Wilder already has her eyes on you and you'll just be putting yourself more at risk. Try, if you can, to get as far away from there as possible. If you can't do that, slowly collect pictures of weird happenings surrounding the Wilder family and contact the police or a private investigator once you have some better information.