The children's mother, Vaneshia Valentine, had also pleaded guilty to negligent homicide before Welsh's trial. She was also sentenced to four years in prison.
the children's mother, 21-year-old Ciarra Johnson, said she left her daughter, Tashae Thompson Johnson, and her son, Clifton Johnson, in the house about 1:30 p.m. to get her hair done.
The fire, which has been ruled an accident, is believed to have started with a heating lamp that the man was using to protect his plants from the harsh temperatures.
The Lafayette Parish Sheriff's Office arrested a Carencro man Sunday after he allegedly set fire to two trucks and a home and then fired several gunshots and three people.