I am Not an expert but I believe "ko" means "child".
Although, I have only seen it used in reference to a
girl/daughter.

Now I have a question for the real experts!
Ranma translates as Wild or disorderly  horse,
but when the two Kanji are combined doesn't
come out as "civil disturbence/riot" or
"free-for-all (fight)" ?

                           Cloudshape