How sweet! I would have answered a bit differently, though, because my Mom is in Heaven too. I would have no, you can't send presents there but you can give presents to someone *here* who is in need, to honor the person who is in Heaven.
I grew up really poor and there were people who helped us. My Mom always told me in later years that she was really glad that I am involved in outreach through my church and stuff because of all those who did it for us. So often now when I am able to do something for someone who needs it, I say "This is for you, Mom."
And yes, I do believe she hears and sees.