Police said the incident took place about 11:30 p.m. on Monday, when the woman was asleep in her Scarborough home, in the Sheppard Ave. E.-Neilson Road area.
The suspect allegedly entered the woman’s home and came into her bedroom. Police said she begged him to leave while holding her son, but the man refused.
The suspect became angry, police said, before grabbing the woman by the throat and punching her multiple times. The baby was also struck on the side of the head during the alleged attack.
Police said someone else — whose identity has not been made public — interrupted the attack. The suspect fled the home still threatening to kill the woman.
On Tuesday police said Richard Russell, 23, is wanted in connection with the assault, and released his picture.
Anyone with information is asked to contact police at 416-808-4200 or contact Crime Stoppers anonymously.