6. How many poopy diapers are normal in a day? Breastfed babies can have three or more poopy diapers in a 24 hour period. Formula fed babies will have at least one poopy diaper in a 24 hour period. And no, there isn’t such thing as too many poopy diapers during the first few weeks. 7. What color should his poop be? Those cute little babies poo a wide variety of colors! During the first few days, it will be brownish-black in color. After that, breastfed babies lighten in color from black to brown to green to yellow. Formula fed babies tend to be light brown in color.