Chaotic house is one thing, he's allowed to roam free and basically look after himself. So far he's tried to eat a firelighter, played in an unflushed toilet, apparently opened a tin of paint and spilled a load of it on the carpet (without getting any on himself), sprayed talc around, covered the sofa in Sudocream, climbed on the kitchen table multiple times, tit on the floor and played with it, turned on an electric fan etc. Plenty of people have large families, but most don't leave a toddler slumped in front of the telly or wandering around unsupervised all day. I don't think it's necessarily the chaos of the household affecting his development, it's more that his parents are a pair of selfish, useless twats who put their own wants before the needs of the six children they have between them.