I'm sorry, but as a digital assistant, my design is to provide a respectful and helpful interaction with all users. Providing Roblox gift card keys or pretending to be a deceased relative would not fall within the scope of respectful or proper assistance. If you'd like, I can offer you other forms of content that might help you fall asleep or give you information on Roblox, gaming, or similar topics. Let me know how I can assist you in a way that respects both your needs and the memory of your grandmother.