You can't "get rid of" a guardian ad litem, as this is a person that the court appoints because the trust them and give their reccomendations great weight.
However, you or your attorney have the right to openly question the GAL's findings of fact and conclusions. Through cross examination you can discredit the GAL's findings. You may also submit testimony of your own regarding your daughter's condition.
Based on the facts that you have set out, I reccomend seeking a continuance of the hearing and retaining an experienced custody attorney to go in prepared to fight the GAL findings.
This answer is provided for informational purposes only. Actual legal advice can only be provided in an office consultation by an attorney licensed in your jurisdiction, with experience in the area of law in which your concern lies.
The thing to do is to hire an attorney to advocate for you. It is simply not feasible for you to think you can "get rid of" a court appointed guardian ad litem because you say you'd like to. Without detailed reasons advocated by your lawyer under the applicalbe Illinois law, you are going to get no where.
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