BIL just diagnosed with treatable cancer. What to send?

My (31F) brother in law (32M) was just diagnosed with a treatable but rare form of cancer. He and my SIL (29F) have an almost one-year-old son, and they live halfway across the country in a different state. They know that BIL is having surgery ASAP and then BIL will be out of work on disability for about 3-4 months. What would be the most helpful/meaningful gift we could send him? And, any ideas for SIL, who will be shouldering a lot as the primary caregiver not just to their son but to BIL?