Does anyone know what a Mental evaluation entails

...? This would be for myself. I do not have any signs of mental illness or instability, but I’m trying to help my ex husband because I and his family believe he is Paranoid Schizophrenic and will not willing seek help. This involves our child and everything is getting worse, and escalating. He’s telling me I need one, and that he doesn’t. I am more than willing to have one done. I am not trying to be facetious or anything like that, but he’s telling me to get a court order from a judge to be mentally evaluated. He won’t do it on his own, if I can do it in my own, then he can and I am trying to prove this point, and to prove I am completely mentally and physically capable to take care of our daughter.