Silas Botwin is Nancy's oldest son.
He's followed in his mother's footsteps, as Silas as proven to be an adept marijuana grower. Also, like his mom, Silas occasionally finds trouble. In season four, he had an affair with a much older woman.
Silas: So, you're the mayor of Mexico or something?
Esteban: Or something, yes.
Silas: I love her.
Celia: You stuck your penis in her. That's not love, believe me.