Tragedy as sister, 5, and brother, 3, both drown when their boat capsizes during family sailing trip as rescuers are still searching for their father

Two young children tragically drowned in Lake Michigan, after the boat their still-missing father took them out on capsized.

Wisconsin father Bill Salnik, 32, took his daughter Charlotte, five, and his son Josh, three, on a sailing trip, and were last heard from at 4pm on Saturday, when they departed from Green Island in Lake Michigan's Green Bay after setting off from Oconto Harbour on Saturday at around 10am. 

The trio, travelling on Bill's boat My Lady Blue, were expected to travel to a marina near Oconto but never made it, according to local officials said. 

Local cops received a report of an overdue boater at around noon on Sunday after Bill, who was from nearby Little Suamico, had not been heard from. 

An overnight search on Sunday night by air and water resulted in My Lady Blue found capsized at 6:22am on Monday just south of Chambers Island. 

Less than five hours later, the bodies of Charlotte and Josh were found around a mile south of where the boat was found. 

Local cops said they would continue their search for Bill, as the warm water and air temperatures have raised the possibility that he may still be alive. 

Bill appeared to be a relatively experienced sailor. 

He posted a video to social media in May showing him taking his two children on My Lady Blue across Green Bay from 'Oconto to Little Sturgeon and back.'

The video showed his two young children merrily snacking as he steered the boat through calm waters. 

Tributes poured in for the young family, with many people reaching out to Bill's family to express their condolences. 

One person told Tina Salnik, Bill's mother and his childrens' grandmother: 'I am so very sorry for your loss. Gods speed to your grandbabies - may they be at peace and in the arms of angels.

'Praying for Billy and all your family.' 

Another said: 'Tina there are no words for the sadness I feel.'