The answer is pretty simple, you can't. A conservatee's child cannot remove a conservator regardless of how egregious he or she may act. But don't worry, I am not finished with my answer.
Judges have the power and authority to remove conservators. So while a conservatee's child can't remove a conservator, he or she can ask a judge to do it by filing a petition. In California, the conservatee's spouse, domestic partner, relative, friend or any other interested person has the right to petition the court to remove a conservator. A conservator of a person or an estate may be removed for any number of causes listed in California Probate Code Section 2650. To keep this post manageable, I am only addressing the catchall cause. It states that a court has the broad authority to remove a conservator if it is in the conservatee's best interest. In summary, just about anyone has the right to ask a judge to remove a conservator and a judge can do so if he or she determines that removal is in the conservatee's best interest. Sounds simple right? Read on.
What does "best interest" mean? What kind of evidence is required? These are the types of questions you should ask yourself before going forward. The answers will differ depending on the type of conservatorship. If a person is being conserved, you might want to gather evidence showing that the conservator committed acts or omissions that put the conservatee's health, safety and/or welfare at risk. This can be difficult if the conservatee lives in a professional board and care facility. The key is to collect and present relevant and creditable evidence. The most emotionally charged persuasive "sounding" argument will fall on deft ears unless it is supported by relevant and creditable evidence.
So how do you remove a conservator? You can do it by filing a petition that is so well drafted it persuades a judge to determine that removing a conservator is in the conservatee's best interest. If the judge is moved, but wants more information, he or she may order an investigation or appoint an attorney for the conservatee. In any event, your initial petition will set the tone. Oh yea, one more thing. Don't forget to nominate a replacement conservator.