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I am a Solicitor and will assist you.
I can confirm that the final order made was a private law order and as such the mother still retains parental responsibility.
I cannot see that the order confers parental responsibility on any step parent - was an additional agreement reached with the mother?
If you don't have such an agreement then you need to seek PR quickly if the child still lives with you - consider applying to the court urgently for a Child Arrangements Order.
I think that the court will be very sympathetic to your situation - especially given that it took 18 months for the mother to see even the child for a contact.
The court will want to retain the status quo and stability of the child residing with you.
You need to apply using Form C100 urgently to your local family court. The court fee is £215. Explain you need PR quickly and ask for an urgent hearing.
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