cas.fulleditmode not working?

Hi, I have the Sims 3 and I need to edit the relationship between the father and the children so that it says son/daughter instead of step son/daughter. The children are his real kids but it got rid of all his relationships when I had to split up the household because he was invisible. After I moved him back in he was acquaintances with everyone so I had to make him remarry the mom but now it says step children. I know that this isn't a big deal for it to say step children but it bothers me because it is his real kids and the mom is pregnant so some will say step and some won't.

Any suggestions?