Who is caring for them if both parents are in jail? Only if the children visit with you here, or both parents agree in writing to change in temporary custody, can you can invoke the emergency jurisdiction of the Florida court. If you can, under the UCCJEA you can move for temporary custody due to abandonment by the parents because they are incarcerated, and the children abandoned. . If not, you should make a call to child protective services in Maryland, ask for a welfare check on the children and advise them of the circumstances and your fear as to who is taking care of them. The state may investigate, and thereafter, file a shelter petition in a dependency proceeding on behalf of the children and seek to have the children placed with relatives such as you preferably before placement in a foster care family. If you are deemed to have a suitable home, after a "home study" is conducted by CPS, the children can be placed with you pending the parents release and satisfaction of case plan goals established by the court as conditions precedent prior to reunification with the children. If neither applies, please contact a family law attorney in the home state of the children to file a private action on your behalf for temporary custody if available. In Florida such a cause exists if you can invoke subject matter jurisdiction over the children while visiting, under the emergency jurisdiction provisions of the UCCJEA- Uniform Child Custody Jurisdiction and enforcement Act- a federal statute- which does not require six months residency requirement for the children here on grounds that an emergency exists due to abuse, abandonment or neglect. The children need only be here one day. Consult an attorney immediately.
Kelly's answer is right on. If they live in PA then that state may have jurisdiction over the children. Florida does have a mechanism for temporary custody to be obtained by extended family under Florida Statute 751. But, you may only have rights to file this form if You may file a Petition for Temporary Custody if: (1) You have the signed, notarized consents of the children’s legal parents; or (2) You are an extended family member who is caring full time for the children in the role of a substitute parent and with whom the children are presently living. The problem here is that the children do not live with you but reside in PA. In Florida, if one of the minor children’s parents object to the Petition, the court shall grant the Petition only upon a finding, by clear and convincing evidence, that the children’s parent or parents are unfit to provide for the care and control of the child(ren). This would most likely work if both of the parents are currently incarcerated.
Of course, you may be able to accomplish this even if the kids reside in PA if both of the parents agree to the same. It's a very complicated area of law. Chances are that PA is the state that would need to determine the issues but you may be able to get them to agree given their current circumstances. I am attaching a link to a Free Florida Form 12.970(a) which is an approved Florida Supreme Court form along with the instructions. (You need to scroll down the page to find 12.970.
12.970(a), PETITION FOR TEMPORARY CUSTODY BY EXTENDED
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