Police have admitted the heartbreaking search for clues about missing Leah Croucher in the Blue Lagoon could last up to 10 days.
It is understood a member of the public saw an item of clothing resembling Leah's distinctive grey hoodie in the water, but did not fish it out.
As the search by diving experts goes into its third day, a police spokesman said: "Police are not in possession of the hooded top.
"Police believe it may be linked to Leah - we are not able to confirm if it definitely is or is not Leah Croucher’s hooded top."
The grey top had a logo saying Stewartby Taekwondo, the club where Leah is a talented member and her dad is an instructor.
Officers say the search for it may last for up to 10 days, and Leah's family are waiting anxiously for news at their Emerson Valley home.
Leah's parents were at the Blue Lagoon Nature Reserve on Wednesday while divers searched the lake and police officers scoured surrounding woodland, read the full story here.
Claire said: "I want answers, but I don't want this kind of answer. So I'm hoping they find nothing.
"But I'm extremely worried," she added.
Claire spoke of the sighting of the grey hoodie at the centre of the search, which bears the logo of the Stewartby Taekwondo Club where Leah's dad is an instructor.
She said: "For someone to finally come forward after seven and a half months and say they've seen the jumper... Up until now there's been no evidence at all."
"This is a very rare jumper. There are only a limited number in existence, so this is a definite possibility."
Leah was last seen in Buzzacott Lane in Furzton, just after 8.15am on Friday, February 15 this year. She was walking in the direction of Loxbeare Drive and Chaffron Way.
Senior Investigating Officer, Detective Superintendent Andy Howard, said: “We are continuing to appeal for information regarding Leah’s movements and whereabouts on 14th and 15th February.
“The Blue Lagoon is a popular public area and if anybody has any information that they believe may be relevant to Leah’s disappearance they will be able to speak to police officers in the area over the coming days.
“Anyone who believes they have information that could assist us is asked to contact Thames Valley Police by calling 101 and quoting reference 43190049929 or Operation Dawlish.
“Alternatively, information relating to the investigation can be left on the dedicated website.”