Dark green poo or black

Dark green poop in a 4-month-old baby can be caused by a number of things, including a diet high in iron, a reaction to certain foods, or an infection. If the dark green poop persists, it is important to speak to a doctor to rule out any underlying medical conditions.

Most babies taking Nan will have green poop. You can search it up here. A lot of mummies shared their concern as well

yes, nan baby poop are green! if you are concerned you can change to friso gold! thats what i did :-)