Web Comic: License for that Butt?

I'm sure that I'm not the only one who does this but I always seem to be knocking over my 3 year old with my caboose. He's just at the right height now and I am not always paying enough attention I guess. I feel so bad and try to watch out but it still seems to happen. I bend over to grab something and he is right there and next thing I know, boom.

(This comic is our copyright, no use without our permission. This was not a sponsored post.)