Dear older brother,
I hope this message finds you well. I wanted to propose an idea for us to consider. Perhaps we could arrange transportation to the mall together next week. Our mother's birthday is approaching, and it would be thoughtful of us to acquire a gift that she would find impressive. Merely purchasing flowers and sweets, as we have done in the past, would be rather uninteresting. Please inform me of your availability.
With affection,
Your sister