I just hatched my first egg from my own hen and rooster. We started out with 2 (the incubator holds only 3 eggs) but one never developed and was discarded around day 10. The other hatched on day 21 but the chick has yellowish stringy stuff hanging out its back end. It was attached to the membrane. Is this normal - should I remove this stuff - is this some known condition? It is just hours old but is moving around and chirping. Not eating or drinking yet -still working on standing but can hold itself upright and scramble around. Thank you.