I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear that this happened.
First, you can rest assured that police are not likely to show up at your house and take you to jail. Filing a false report with CPS is a state jail felony, however it's the type of thing where they will typically send you a notice in the mail with a court date, asking you to appear voluntarily. They do not make you wait in jail for that appearance, unless maybe you had a history of filing false reports. Now, just the fact that a report turns out not to be substantiated when CPS arrives doesn't mean it was a false report. They have to prove that you knowingly made up false charges, and since you were relying on what your children were telling you, I don't know that they'll be able to do this. See Tex Fam. Code, Section 261.107. You'll be able to call the children to testify as to what it's like living with their father. Also, just because he calls and files a report doesn't mean the DA will press charges. Many cases referred to the DA do not result in any sort of criminal proceeding. I know it's tough, but try not to worry about it unless you hear from police.
Second, if police contact you, you have NO OBLIGATION WHATSOEVER to talk to them. You can refuse. They cannot hold your refusal against you, because it's an absolute right. And if you choose to talk to them, you can insist that a lawyer be present to protect your best interests.
Third, you have a constitutional right to be represented by an attorney any time it's possible that you'll be denied of liberty. That means, when you go to the court appearance, you can ask the judge to appoint a lawyer for you at no charge. Your lawyer will enter a plea of not guilty on your behalf and request bail. Then you go prepare your defense and go back to court for a trial. If you don't have a criminal record, jail is pretty unlikely for this type of offense. More likely, you'd serve a term of probation, pay a fine, and maybe do some community service.
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