when i got up this morning i didn't hear any chirping so i went down stairs real quietly so not to scare em and was horrified to find my cat laying inside the brooder. as i yelled i woke up the chicks and they were all fine. and my cat new she was in trouble she, wanted out but couldn't. there was a tiny gap on the lid that is usually covered, she must have squeezed threw. I am not sure how long she was in there but there was no way out. brooder is now kept shut with heavy paint cans!!