I think I have this all together, buy wifi, put on airplane mode, use ship internet, use whatsapp with my brother, check my carrier for coverage in the islands.
If anyone has other suggestions, please add. To the folks that have helped me, I can't thank you enough, I haven't sailed without mom in 15 years..at 97 she is too unsteady to join us after a hip fracture (while on a cruise) and recovery and I am just worried to be away. Every reply has been so helpful as mom insists we go without her. Thank you all so much.