Helping out as an E-2?

[ck98]

I am currently on an E-2 visa and I am curious as to know if its possible for me to help out at my parent's business without pay? (Example: Take charge of the cashier from time to time). Do to the fact that I'm basically volunteering to help them out without being compensated, would this be alright?

[inadmissible]

According to the letter of the law, no. In practice, I suppose who would ever find out eh?