"It is now been five weeks since we last saw Liam and the prospect of Christmas without him is a really difficult situation for us to face. We understand the public's interest and we really do appreciate the support everyone has given by sharing the posts and putting up posters. Police officers have been out searching the areas that Liam was last seen every single day since we reported him missing and we are truly grateful for everyone's perseverance in trying to locate him."
Alix added: "We continue to hope that Liam will be found."
“We have had an overwhelming response to our appeals and more than 200 sightings of Liam have been reported. Every piece of information has been followed up but despite extensive enquiries and intensive searches carried out Liam is still missing. Our enquiries still suggest he would have travelled to the Crathes area. We urge residents, particularly in this area, to remain vigilant and report anything unusual to police."
“Intensive searches remain ongoing and will continue with the exception of Christmas Day. We know that many people have offered to assist with searches however we carry out these operations in a highly specialised, methodical way with officers who are trained and experienced. We have a plan in place to ensure that all the challenging land we need to cover is searched effectively with the use of the required specialist resources."
“The public in the North East and particularly the Banchory and Crathes communities have been incredibly supportive and we are very grateful for the assistance and support that has been provided."
“Regular reviews of the enquiry have been carried out and will continue as is standard with any long-term missing person investigation."
“We have remained in contact with Liam’s family and will continue to keep them updated.”
He has short brown hair and walks with a distinctive gait.
When he was last seen he was carrying a camouflage North Face rucksack and was wearing Nike Air Max trainers.
He bought Lucozade, Jaffa Cakes and Dairy Milk at Sainsbury's at Guild Street before he walked through Union Square to get the CCTV-less StageCoach bus at Aberdeen Bus Station.
Anyone with information are to contact Police Scotland on 101.