Alongside dozens of official searchers including Police Scotland staff, mountain rescue experts and coastguards who took to the beach while the Queensferry RNLI lifeboat was offshore, members of the community felt compelled to help Mikaeel's frantic family.
Between the three-year-old's home in Drylaw where he was last seen, tucked in at his usual bedtime of 9pm, and the sea, there are a thousand places he could try to shelter.
Builders on one site close to his home shut down operations as they searched in scrap bins and under half-laid floorboards when they heard the news.
A police helicopter homed in on one after another of the overgrown and waterlogged waste grounds that punctuate the new housing and factory developments across the north of Edinburgh where the search centred.
The hunt for Mikaeel, who was described as a "friendly and playful wee boy" among friends, escalated throughout yesterday after his mother found his bed empty at about 7am when she went to wake him up as usual for school.
The infant, popular at Flora Stevenson Primary School nursery in Stockbridge, went to bed in nightclothes, but a jacket and a pair of shoes were missing along with him.
Concern over his disappearance reverberated across the community and head teacher Irene Brennan told parents in a letter: "I understand why you may be concerned but it is important to recognise that it appears that Mikaeel went missing from his home.
"I would like to reassure you that the children are safe in our school and we are reassuring them about their own personal safety.
"As well as supporting our children, our staff are also supporting the police with their enquiries. We are keeping in touch with Mikaeel's family and our thoughts are with them at this difficult time. I am sure you will join us in hoping that he will be found safely in the near future and returned to his family."
Police hoped that by releasing as much detail about the boy as possible it would help the search.
He is described as having a faded scar on the bridge of his nose and a sore on the left hand side of his mouth.
He may be wearing his grey pyjama top with an embroidered turquoise dinosaur on the chest and also have with him black gloves with multi-coloured fingers.
Last night, police issued a new image of the missing boy in a beige jacket he was also believed to have been wearing as enquiries continued.
Police Scotland Superintendent Liz McAinsh said the family was distraught.
Ms McAinsh said: "They say Mikaeel is a friendly, playful wee boy. They are obviously concerned for his safety as well and will do everything they can to help us in finding Mikaeel."
People are being asked to urgently check all property including gardens, outbuildings, garages, sheds and vehicles.
Temperatures in Edinburgh were about 2.3°C (36°F) both last night and the night before.
Robert Pearson, chairman of a local residents' group, said that he sent out a plea for help earlier and around 50 people responded.
He said: "We split up into groups of seven to search the area. My group of seven are currently going through the Silverhouse Golf Course at the moment but we are fearful and wary of the fact that we might not have much hours left of light as it begins to get darker.
"We are liaising with Police Scotland and will continue to do so until they say it is unsafe to carry on searching. At the moment they have roughly 70 officers searching the area.
"However, the mood among the volunteers is that it is feeling quite desperate now."
Neighbour Linda Slattie, 52, said: "We were out this morning looking, down to Muirhouse Park, the community centre, looking in bushes and lock-ups and things like that.
"I've been very shocked. It could be any one of our kids."