Dear [Younger Brother's Name],
I hope this letter finds you well. I am writing to you because I am concerned about the friends you have been spending time with lately. It is important for you to understand the impact that bad company can have on your life. Here are some reasons why you should avoid bad company:

Negative Influence
Bad company can have a negative influence on your behavior and decision-making. When you surround yourself with people who engage in harmful activities such as drug use, violence, or dishonesty, you are more likely to be influenced to participate in these activities as well.

Reputation
The company you keep reflects on your reputation. Associating with individuals who have a bad reputation can tarnish your own reputation and make it difficult for you to build positive relationships with others in the future.

Legal Consequences
Engaging in illegal activities with bad company can have serious legal consequences. Getting involved in criminal behavior can lead to fines, imprisonment, and a criminal record that can follow you for the rest of your life.

Personal Growth
Surrounding yourself with positive influences will help you grow as a person. Good friends will support you in achieving your goals, encourage you to make responsible choices, and help you become the best version of yourself.
I urge you to choose your friends wisely and surround yourself with people who uplift and inspire you. Remember that true friends will always have your best interests at heart and will support you in becoming the person you aspire to be.
Take care and make wise choices.
With love,
[Your Name]