I cant figure this song out for the life of me!!!?

ok so this may sound cheesy but i sang this song in choir once when i was like i dunno somewhere between 13 and 15 its a really sweet song that i think was actually written for someone that was dying of cancer or...... no idea but it was written for a little girl. its about friendship it says things like ill be there .... something about the sun and happiness omg i know very vague but if only SOMEBODY can take my itty bitty little clues and figure out wut song im talking about i would ALMOST be willing to pay them lol. please help!!