Kitty not always using cat box


Good even all. I could use some advice.

We have a total of 4 cats. Adopted two and two that are brothers that we were given to us from someone that had found kittens at a Wal-Mart. Wal-Mart was ready to call the humane society to come and get them and thier mother. All got homes (thanks to a lady) We got the last two. Now they are about 6 to 7 months old, males.

My problem is that one of the brothers decides at times that he is not going to use the little box! One time was even right after we changed the littler boxes, so, it isn't because the boxes aren't clean.

I think it is a territorial thing but I am not sure. However, I am very tired of this and would love some advice. Please!