That's the depressing conclusion of new research that has discovered a relationship between too much toddler screen time and nursery risks for poor motor skills and psychosocial difficulties.
Professor Linda Pagani, from the University of Montreal, led the study and says the finding highlights the need for parents to adhere to national guidelines which say children around two-years-old should watch no more than two hours of TV a day.
She said: "This is the first time ever that a stringently controlled associational birth cohort study has looked at and found a relationship between too much toddler screen time and kindergarten risks for poor motor skills and psychosocial difficulties, like victimisation by classmates.
"These findings suggest the need for better parental awareness and compliance with existing viewing recommendations put forth by the American Academy of Pediatrics.
"The AAP discourages watching television during infancy and recommends not more than two hours per day beyond age two. It seems that every extra hour beyond that has a remarkably negative influence."
Looking at 991 girls and 1,006 boys in Quebec, aged 29 months, whose parents reported their television viewing behaviour as part of a child development study, Professor Pagani found that if a child watched up to two hours and 52 minutes of TV - compared to an average of one hour and 45 minutes - the child is unlikely to suffer any negative effects.
But the results showed that the children who watched TV for more than three hours were falling behind when it came to talking and numeracy.