was falsely accused of child abuse. I am a loving parent, but how can I defend against these claims?

I am not sure from your question if the accusation of abuse has arisen out of a child custody matter or if it is a criminal matter.  Most lawyers would handle those two issues in completely different ways.  There are many considerations, nature of the alleged abuse, witnesses, time frame, age of child, timeline of accusation, etc.  I am not asking the particulars of your sitation in this setting as if it involved a criminal matter, then it would be important not to post details surrounding the matter online.  If this is a custody issue, then it may be to your advantage to have a guardian ad litem who can talk to the child.  Depending on the circumstances, it may be advantageous to involve experts such as psychologists or pediatricians.   I would point out to you that a lawyer who becomes aware of the abuse of a child has a legal duty to report that abuse to CPS.  Although you are protected by confidentiality in what you say to your lawyer, confidentiality does not apply to abuse of child.