Answer:
The answer is: Stewie can't report any taxable income and Brian can report a $1,000 loss.
Step-by-step explanation:
Since Stewie is doing the activity as a hobby, he can't report a loss on it. It's like someone who likes to play basketball on weekends with his friends, he can not report the cost of a pair of sneakers and a ball as a loss.
Brian on the other hand runs a business and actually lost money doing it, so he can deduct his losses form his gross income.