Brief Answer:
It's normal if not persistent

Detailed Answer:
Hi

Thanks for asking on Ask A Doctor platform

I have gone through the query and do understand your concern.
In infants till 6 months of age, change in consistency and color of stool is normal.
The green colored stool contains biliverdin which gets converted to stercobilinogen (responsible for yellow color of stool) in presence of some enzymes/healthy gut bacteria.
Sometimes green colored stool is due to introduction of formula feed or any other food items and it normalises witjin few days.
I won't get worried for green colored stool if it's not too watery, frequency is not too high, oral intake is good and baby is otherwise active.
You can give some probiotic like Enterogermina or Econorm one daily for 3-4 days.
Watch for any abnormality in stool or persistence of green colored stool, blood or mucus mixed stool etc.
If you find any abnormality please consult with your doctor.

I hope this helps.
Please let me know if you have any more questions.
Regards

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