Thank you for your response.
My apologies for my delay in responding to you.
To put your case in the court arena - you would need to complete Form C100 - asking for a Child Arrangements Order for both girls to live with you. This would be the correct thing to do as currently you have no parental responsibility for the girls.
The court would make a decision as to whom the children would live based upon the best interest of the girls.
A positive for you is that the girls have lived with you for so long. The girls stability is with you.
On the other hand - the court will take into account the wishes and feelings of the girls. When a child reaches around the age of 13/14 (older for some, younger for others) they will often consider a child to be Gillick competent. The court will then give strong regard to the wishes and feelings of the child. If the 13 year old is clear that she wants to live with her grandparents then the court will give strong regard to such a wish in light of her age and understanding.
Courts do not like to spilt siblings. If the 13 year old wanted to go then it would be highly unusual for a court to separate the siblings.
In reality therefore it is likely that the court would approve the children living with their grandparents on the proviso that it is safe for the children there and there are no child protection concerns. That being said - I do think that your case needs to go to court. I am not sure of the timescale of the planned move of the grandparents and in the interim you do need parental responsibility. The grandparents will also need parental responsibility if the children live with them. The only way for either you or the grandparents to obtain parental responsibility is by court order.
Do let me know if I can help you further.
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