https://www.healthychildren.org/English/family-life/Media/Pages/Why-to-Avoid-TV-Before-Age-2.aspxhttp://www.washingtonpost.com/national/health-science/blue-light-from-electronics-disturbs-sleep-especially-for-teenagers/2014/08/29/3edd2726-27a7-11e4-958c-268a320a60ce_story.html