Report 12836: Family hears vocalizations and finds footprints in their backyard east of Pekin

I have pictures of very large footprints outside our house when my brother was camping here. He said he heard something outside the tent and came inside.  We checked the next morning and found very large footprints right outside of the tent. The night before he thought he heard deer there, but these were no deer tracks.  We have deer here all the time. My daughter and I had heard a low growl a couple of nights before this.  The whistles that we heard earlier this month also sound like those that we heard on your website.