Addressing this situation requires sensitivity and open communication. Here's a step-by-step guide on how the adult brothers can approach their parents to discuss their concerns about being called multiple times a day:

1. Choose the Right Time and Place: Find a suitable moment when both brothers are together and free from distractions. Make sure it's a time when everyone is relatively relaxed and not in a rush.

2. Express Understanding and Gratitude: Start the conversation by expressing love and gratitude for their parents. Acknowledge that their parents care and want to stay in touch, which is appreciated. This sets a positive tone for the conversation.

3. Share the Concern: Be honest but gentle about how the frequent calls impact their daily lives. Mention that sometimes it becomes challenging to handle multiple calls during busy work or personal schedules.

4. Emphasize Independence and Responsibility: Remind the parents that both brothers are adults now, and they have grown capable of handling things independently. Assure them that they are responsible and will stay in touch, but maybe not as frequently throughout the day.

5. Offer Alternatives: Propose alternative ways of staying connected that would suit everyone's schedule better. For example, suggest having a designated time each day or every few days for a more extended catch-up call. This way, the parents won't feel ignored, and the brothers won't feel overwhelmed.

6. Reassure Love and Care: Reiterate that this request is not a reflection of their love for the parents. Reassure them that they care deeply and value the relationship, but they want to find a balance that works for everyone.

7. Boundaries and Compromise: Setting boundaries is essential in any relationship. Encourage open communication and compromise on the frequency of calls that everyone can agree upon.

8. Patience and Understanding: Understand that change may not happen overnight. The parents might need time to adjust to the new communication pattern. Be patient and give them the space to adapt.

9. Stay Consistent: Once an agreement is reached, both brothers should stick to it and not give mixed signals. Consistency will help reinforce the boundaries in the long run.

10. Reinforce Love and Appreciation: Regularly remind their parents of their love and appreciation. This helps maintain a strong emotional connection despite the reduced frequency of calls.

Remember, open and honest communication is crucial in any relationship. Approach the conversation with empathy and a genuine desire to find a solution that works for everyone involved.