mother-of-three georgina rojas-medina , 41 , was shot and killed by her common-law husband on saturday night .
gerardo tovar , 44 , then turned the gun on himself in tulare , california .
the couple 's bodies were discovered by their 4-year-old daughter who walked out of the house and asked a neightbor to call the police .
the 4-year-old girl and two other siblings , ages 10 and 12 , were not hurt in the shooting .