Custody Orders do not expire.
If you are concerned about your ex coming to get your child, you should file a Petition to Modify Custody citing the significant change in circumstances since the last Court Order which gave him custody. However, since you are asking the Court to change its decision be sure you can prove that you have done an excellent job caring for your child. At one time the Court thought that the child would be better off with him and therefore you will need to show that your child has done well (physically, emotionally, etc.) with you. Be prepared with pediatrician's records, witnesses, and pictures to prove your case.
You should discuss this with a California attorney as soon as possible.
A child custody order doesn't expire, but if circumstances have changed since it was granted, you can seek to modify it. If your husband failed to exercise the sole custody that was awarded to him a year ago, and he knew where you lived and your telephone number, his failure to exercise his custodial rights, coupled with your good parenting of your child, could constitute a change of circumstances to justify an Order to Show Cause to modify child custody. Because the Court granted sole custody to your husband, it is likely that your husband presented evidence of some improper parenting by you. You should take steps to demonstrate that whatever your problem had been, it has been corrected, and that you have been an exemplary parent. Among other things, you should enroll in a parenting class, complete it, and attach a copy of your certificate of completion to your Declaration in support of your Order to Show Cause to demonstrate your good faith actions to remedy whatever problem that resulted in your prior loss of child custody.
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