A man was stabbed to death in a "frenzied and wordless" attack after asking a young father if everything was alright with his crying child, the Old Bailey has heard.
Jurors were told 63-year-old Alan Smith was stabbed five times in front of his partner and daughter as "revenge" for the enquiry.
He was at the BB Cafe in Leyton, east London in March last year when he asked Matthew Quesada about the crying child.
Prosecutors said Quesada swore at Mr Smith, who took his family to the nearby Roma café.
The court was told Quesada went home, picked up a knife from his house, and then returned to carry out the attack on Mr Smith.
Quesada was found in a car with his mother the next day. He had cut his hair, and had his passport with him and details of flights to Brazil.