Her sister Nicola Bulley says there is “no evidence” she fell into a river.
The missing mom disappeared on January 27 and has been missing for over a week.
Nicola had dropped her daughters, aged six and nine, at the local village school before going for a walk near the River Wyre at St Michael’s in Wyre, Lancashire with her dog Willow.
Police said yesterday that the main theory they are working on is that her death was a tragic accident and that she may have fallen into the water.
But Nicola’s sister Louise Cunningham encouraged the public to keep an open mind in a Facebook post last night.
He wrote: “On the back of the latest police media update, I can add that there is no evidence that he has gone into the river, it is just a theory.
“Everyone should keep an open mind, as not all CCTV and evidence has been fully investigated, police have confirmed that the case is far from over.”
Speaking at a press conference yesterday, Lancashire Police Chief Superintendent Sally Reilly told reporters that their “main working case” is that Nicola fell into the River Wyre and that it is “not suspicious, but a tragic case of a missing person”.
He gave an updated timeline of the mortgage adviser’s last known movements, saying he was seen on the river path at 8.43am. after dropping off her children at school.
The mother-of-two was then seen walking her spaniel Willow around the downfield minutes later at 8.47am, before emailing her boss at 8.53am. and join a Team call at 9.01am.
At 9.10am, she and Willow were spotted in the upper field and police believe her phone was on a bench while it was still connected to the teams meeting at 9.20am.
The press conference came hours after Nicola’s partner Paul Ansell spoke to the press and compared her disappearance to a “dream”.
He told Sky News: “It seems absolutely impossible. it’s like a dream, i can’t get over it.
“I have nothing to say other than what the family said yesterday, my whole focus is on my two girls and staying as strong as I can for them.
“I’m afraid if I focus on anything else, it will take my focus away from that.”
Paul added that he “doesn’t know how he does it”.
Contact our news team by emailing us at webnews@metro.co.uk.
For more stories like this, check our news page.