Legal Question in Family Law in Florida

In general, Florida does not recognize grandparent rights in child custody situations. You can petition the court if both the parents are "unfit," however, that is an extraordinary challenge to prove. Poor judgement does not qualify as being "unfit," nor are any of the other factors you discussed. Unfit is not feeding the child, physically abusing the child, the child being secually abused in her care, etc. Without a doubt, at this point you cannot stop her. You would have to wait and see how she is cared for after she leaves. While your home may be "better," that has no legal relevance. In Florida, a parent has the right to raise their child as they see fit, with the few exceptions discussed above.