The search for the child has gone into its second day, as investigators are "extremely concerned" for the baby’s wellbeing in the sub-zero temperatures.
Police began the search after Ms Marten, 35, and Mr Gordon, 48, were found by police in Stanmar Villas, Brighton, late on Monday night (February 27).
The pair had been missing for 54 days with the child after their car was found burning on the M61 in Bolton, Greater Manchester on January 6.
The couple were discovered without the baby they had been travelling with, leading to a mass outdoor search for the young child, which police believe could still be alive.
Metropolitan Police teamed up with Sussex Police to search 91 square miles of open land in Sussex late into last night.
Sniffer dogs, drones, a police helicopter and thermal imaging cameras are being used in the search.
Police say the lack of information at this time means they now have to consider that the baby has come to harm, as searches continue.
Eddie Mitchell was with the search teams this morning and here are the photos...
The pair had been missing for 54 days with the child after their car was found burning on the M61 in Bolton, Greater Manchester on January 6.