Phillip Ocheltree left his home with his family to escape tornadoes
Motorists jumped into rushing floodwaters in Texas to pull a toddler and baby from an overturned car and help to resuscitate them as tornadoes hit the state.
In video footage, the family's SUV can be seen upside down and partially submerged in floodwaters near Myrtle Springs as passers-by desperately try to force the doors open to rescue the children.
Phillip Ocheltree had left his home with his family to escape tornadoes which hit the area over the weekend, but his vehicle aquaplaned on the road and flipped into a ditch on Saturday.
His two children were trapped inside the car until passing motorists waded into the fast-flowing water and managed to get them out.
Distressed calls of "Breathe, breathe" can be heard in the footage as CPR efforts begin.
On his Facebook page, Mr Ocheltree said on Sunday that his baby son, Marshal, was doing well in hospital and his two-year-old daughter Addy was "stable and doing much better".
He wrote: "Still under sedation but pulling the breathing tube in the morning to see if she can do it on her own.
"All scans and tests say it looks promising, we seriously cannot thank all of the friends, people family everyone that has been with us thank you all for your support and prayers the man upstairs is hearing them loud and clear."
At least 14 people have been killed in the Midwest and the South after storms triggered tornadoes and flooding over the weekend.
Melanie Espinoza Rodriguez (2) died in Tennessee after she was struck by a football goal post picked up and thrown by the strong winds.
A seven-year-old boy was also killed in Mississippi after he was electrocuted when he unplugged an electric golf cart and dropped the lead into water on the ground.
In Arkansas, a 10-year-old girl drowned in Springdale and the body of a woman who disappeared while riding on an inflatable ring was found in a creek in Eureka Springs.
Cove Creek volunteer fire chief Doug Decker was killed on Sunday morning after he was struck by a vehicle while checking water levels on Highway 25 near Quitman.
Rescuers in the state are still looking for an 18-month-old girl and a four-year-old boy who were in a vehicle swept off a bridge by floodwaters in Hindsville.
Search teams have been going door to door in Texas after up to four tornadoes hit several small towns in the east of the state, flattening homes, uprooting trees and overturning vehicles.
The storms have cut a swathe of destruction 35 miles long and 15 miles wide in Van Zandt County, around 50 miles east of Dallas.
Interstates were closed in Missouri and Kansas as the storm brought flooding and heavy snow to some areas.
The governors of Missouri and Oklahoma declared states of emergency due to the flooding.