My suggestion would be if you know she cant pick up son or is out of town. Get your child do no text her you got him or when to exchange keep him and let her call you and ask or say you got our son i will get him and so on. You know what I am getting at.Its when we tell them what we doing i think they have control over us and like the idea they can do what they want and we are here to wait it out.
Maybe tell her you rather tell her upfront if she cant be with son instead of lie about it. You dont mind your son staying with you its my child so I rather have you tell me the truth so I can spend quality time with my child and bond with him.
What do yo uthink about that?