Complex sentence: Chlumsky entered show business at an early age, modeling with her mother in an advertising campaign, though her roles in "My Girl" (1991) and "My Girl 2" (1994) brought her fame.
Split into simpler sentences: Chlumsky entered show business at an early age, modeling with her mother in an advertising campaign. Her roles in "My Girl" and "My Girl 2" brought her fame.