Guardianship

I live in Florida and my little godsister is coming to live from the Caribbean Island. Will a notarized letter from her mom stating that I will be taking care of her serve as proof of guardianship. What is the proper procedure in the state of FL for guardianship?

A child wants to leave his aunts house and move back with his mother. They have custody of him. Can he tell them he is leaving if he is 15 years old?

A child wants to leave his aunt's house and move back in with his mother. The aunt has custody of him. Can he tell the aunt that he is moving back to his mothers? He is only 15 year old.

I am the guardian of my three grandchildren, ages 13, 11 and 6. My son passed away after a fight with cancer in 2002. His ex-girlfriend left him with the children when he was sick (and she left him many times before to care for the children). My son had sole custody of the children and she signed guardianship to me when he passed away. Now the mother of the three children has remarried (1 yr) and has filed a petition to terminate the guardianship. She has heard about the social security money through other sources and I think that is her main interest (also earned income on tax returns). Last year was the first time of regular visitations. What are my rights and what can I do to keep the children. The children go to a good school and are in many activities. All of this would stop. They would have to change schools and have a very unclean surroundings as I have heard from the children.

If my husband and I were to die, what papers would we need on hand to give custody to a certain set of grandparents?