Missing my son...

I was in a line at the supermarket the other day, and uhm... y'know, I had gotten my skim milk, and a dozen eggs and a loaf of bread. I am about to start assembling all my little things on the conveyor belt over there. And the lady in front of me that is... well, she' is flat out staring at me. She continues this and I'm getting a little nervous and uh, she continues to stare at me. And I stop a bit and sheepishly, I keep looking the other way. She inches closer and closer and she says to me: "I apologise for staring, that must have been annoying. It's just that you look so much like my son. He died and I just can't take my eyes off you." She pulls a tattered photograph of her son out of her purse. He looks absolutely nothing like me. In fact he's... Chinese. Well we chatted and continued our light banter. As it was wrapping up she says: "I'm sorry, I have to ask you. Would you mind, as I leave the supermarket here, would you mind saying "Goodbye mom" to me? I, I know it's a strange request but I haven't heard my son saying "Goodbye mom" to me, and it would mean so much to me to hear it. And I said: "Well, you know, okay, yeah, sure. Eh.. uh... I can say that." And, and so, she uh gets her groceries all checked out. And uh, as she's going out the door she waves at me and she hollers across the store: "Goodbye son!" And I look up and I wave and I say: "Goodbye mom!" And there she goes, and I go back to assembling my few little things on the conveyor belt and the clerk checks out my things. And uh, and he gives me the total and he says: "That'll be four hundred and seventy nine dollars." Uh... and I said: "Well, how is that possible! I've only got some tuna fish, and uh some skim milk, and a loaf of bread..." He goes: "Well, well you're also paying for the groceries for your mother. She uh, told me you'd take care of the bill for her." And I said: "Well, wait a minute! That's not my mother!" And he says: "Well I distinctly heard her say as she left the store "Bye son!" and you said "Bye mom!" and so what are you trying to say here, uh..." I said: "Well, JESUS!" And I looked out into the parking lot and she was just getting into her car. And I ran out there. And she was just closing the door, and she had a little bit of her leg sticking out of the door and she was pulling away and I grabbed her leg and I started PULLING it! Much like, i'm pulling yours...