Det Ch Insp Charlotte Whalley from GMP said: “As part of our enquiries, we’re working to establish who Ava’s mum is.

“We are continuing to appeal for her mum, who may require medical assistance, or her family, to come forward and speak to us.

“We believe that there is someone out there now who knows what happened. Please know that we have trained officers ready to support you.

Police have again appealed for more information, asking people to “cast their minds back to previous months”.

“Perhaps you heard something, or saw something that didn’t feel right.

“It may have seemed insignificant at the time, but knowing what you know now, come forward. It could be crucial to finding the truth for Ava.”