Have no idea. Slang changes from generation to generation. I drive a school bus, and one of my black students, says "later dog" when he got off the bus to me. I was pissed. When I was growing up calling a woman a dog, meant, she was ugly. His friend later told me it was meant as a compliment. because dogs are loyal, and your friend. hell, I was realy confused then. I didnt know, if he was covering up for his friend or if it was true.
Non of those, it`s a cry from the heart for his real mama whom he sees in you. Best compliment ever!
Watch "count blackula" and decide for yourself.