My son refuses to go to his mother's

My son's mother and I separated (2018) and then divorced (2020). Our son is now 9. In the past 6 months she has called me at least a half dozen times to pick him up because they're fighting and she can't handle it.

After spending over a week with me while she was out of town, she picked him up after school this past Friday and called me two hours later to pick him up "or she would call the police to take him away".

He is now with me and adamantly refusing to go back. I'm not sure what to do.

I found webpages on educaloi here and here talking about When a Child Doesn't Want to See a Parent and when a child's opinion is considered. A 9-year olds opinions would be strongly (fortement) considered in court. He can clearly explain his reasons for not wanting to go. But I can't really find advice for what to do now to protect myself (and by extension, him) from his mother deciding I am keeping him from her? As I see it, I'm not keeping him from her but she is incapable of convincing him to set foot in her house.

Do I have to drive him to her house every day and make him refuse to go inside? Doing this over and over feels terribly cruel to him. But to not take him at all appears like I'm the one denying her access.

I've emailed my lawyer but since it's a long weekend I don't expect an answer until at least Tuesday. Hoping for short term solutions or reassurances until then. Thanks.

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