Concerns are growing for a missing married mother-of-three who is suffering from post-natal depression.
Karen Simpson, 31, of Burscough, Lancashire, left her home on Sunday morning to walk to a local Tesco store.
She was seen leaving the premises in Liverpool Road North at about 11am but did not return to her address in nearby Elm Road as expected.
Her sister Clair Dobrec said: "We are devastated by Karen's disappearance which is very out of character. She had been suffering post-natal depression, for which she was receiving help but this is one of the reasons we are so concerned for her.
"I want to say to directly to Karen, if you see or hear this appeal, we know you haven't been feeling well and we want you to know that we are all here to support you. We are so worried about you, we are all missing you, especially the children - we just want to know you are safe.
"We have been overwhelmed with the support from the local community and we are so grateful to everyone who is out helping with the search for Karen."
Mrs Simpson is married to husband Philip and has two boys and a three-month-old girl.
Detective Chief Inspector Andrea Barrow said: "Both we and Karen's family are growing increasingly concerned for her welfare and so I would urge anyone who has any information at all or thinks they may have seen her to get in touch with us.
"Similarly, I would urge Karen herself, if she sees or hears this appeal to contact someone to let them know she is safe.
"We have a team of over 70 officers working to try and find her along with a team of over 100 volunteers from the local community who have come out to help which has been a huge support to both ourselves and Karen's family."
Mrs Simpson is described as being white, around 5ft 6in, of slim build. She has dark brown hair which is dyed red at the ends. She was wearing a dark green padded jacket, blue jeans, maroon grey scarf and black ankle boots.
Anyone with information should call police on 101.