My 4 year old son got up and called me at variable hours, sometimes even in the middle of the night! With this alarm clock that requires no time to read, now he knows when he has the right to get up to go quietly watch cartoons or read or play quietly in his room. He loves because he has the feeling of being more independent. In addition he sleeps longer, as at first he watches the passage rabbit "Day" but then he does not expect more ... and goes back to sleep. Brief though it is a little expensive, which made me hesitate a long time before buying, it reveals a good investment: suddenly I'll buy a second to put in grandparents or a third since the youngest 2 years claims it.