Hi I can fully understand your worry
Just passing green motion is not sign of infection. If child has no fever, is active playful, and feeding well not to worry.
As you mentioned you have started new diet... that itself can induce faster intestinal movement...as it's something new for babies body... so the Bile pigment does not get enough time to undergo all process... wherein it changes colour from green to yellow.... That's is possibly the reason I your case. I HOPE YOU WILL BE SATISFIED WITH THE ANSWER.
Next Steps
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