Laughing Seizures?

My daughter is almost 3 and is having what I think may be seizures. She will arch her back, make fists with both her hands and laugh (sometimes grunt or squeal), she will either close her eyes or they will go up and to the right. These episodes last only a few seconds but many times will happen several times back to back. They seem to occur most frequently at night, when waking or going to sleep. When they do happen during the daytime she will seem very tired afterwards but is alert and somewhat responsive. Does anyone else have kids that have episodes similar to this? I am going to call her neurologist tomorrow to see what he thinks. She has never been diagnosed with seizures but is followed by a neurologist because she has a mitochondrial disease. Thanks for any help.