DS has always been quite an independent little man, happy to play on his own if I was busy and very active and keen to crawl around and explore without me. But suddenly in the last 2 weeks he's become extremely clingy. Some days I literally can't put him down all afternoon or he screams and cries like he's really distressed. It's such a contrat from his normally behaviour. Does anyone have any idea what could be causing it? Or any ideas on the best way to respond?