Around 4:45 a.m. Thursday, authorities say the suspect knocked on the door of the woman's home in the 3700 block of Daintree Park Court, off Tamarron Parkway, and got into an argument with her.
He left and she called 911. The suspect returned, this time getting into a fight with the woman's new boyfriend, who was also at the house.
According to officials, that's when the suspect stabbed the boyfriend inside the home.
The woman's three children, who are ages 2, 4 and 12, also live at the home with her.
The suspect is the father of the 4-year-old and 12-year-old. The stabbing happened in front of them.
The suspect left the neighborhood in a silver car with another person. He made it a few miles before he was stopped on FM 1463 and taken into custody.
Detectives tell Eyewitness News they do not believe there was any kind of restraining order against the suspect. He and his ex were apparently separated for at least two years before Thursday's attack.
Fatal stabbing update