If grandparents care, they can send some nutritional and health products such as milk powder and cakes. If you are in the north, you can also send warm clothes and knee pads to prevent the elderly from getting rheumatism. This is very practical. Parents can take them to buy suitable clothes or fruits. If parents cook by themselves, they can buy a good bag of rice or flour. In fact, it doesn't matter what you buy, but filial piety is the most important thing. Buy it yourself.