Dr Caspar Addyman from Goldsmiths, University of London is an expert on why babies laugh and author of The Laughing Baby ... laughs in one day from her twin boys and many parents have told ...

3-4 months: First giggles Babies start laughing as young as three-months ... a stand-up comedian and dad to twin five-year-old boys. “I remember when the boys were really into rainbows, I ...