In which my children become the family pets.

I do not know what is wrong with my children tonight. We got home and they were upstairs playing, Ainsley came downstairs and said Renah peed in her bed. Renah said it was because Ainsley told her to. Then a few minutes later Ainsley came downstairs to get some plastic bags to clean up poo. I yelled for Miley to get in the crate thinking she had gone upstairs. Nope, Ainsley told Renah to poo in the floor and they thought it was funny. Yes, they did get in trouble and sent to bed. I am frustrated as Ainsley is almost 6 and acting like this. This is the only bathroom incident, but not the only thing they have done lately that have made me question what is going on with them. I know they are still young but really they are smart kids and acting like crazy ones! Is it a kid thing, or a jealous thing because of the baby? I have no idea but this cannot keep going like this or I might pull my hair out before school starts again!