Any advice should I introduce fish porridge to my son of 6months? He has just started solid food about 2 weeks ago, whereby I gave him veg + porridge. But these 2 days, I gave hime fish + porridge. He seem having difficulty to pass motion. Always cry. Stool is sticky & not very hard. Is this sign of constipation? He does not like to drink water. Can he drink prune juice dilute in water?