Just think about it. A craved egg with an ostrich head/ neck sticking out and wearing the top of it's egg shell on it's head. For an unposed female, maybe you could place it next to her belly as if she had been warming it. As for the male...maybe underneath it like it had been protecting it while it hatched?

If someone could draw some concept art, I would really appreciate it for I draw about as well as a toddler with a fistful of crayons.