In ''good old days'' (back when there were only two channels in TV) Polish children were going to bed after ''dobranocka'', but nowadays the ''dobranocka'' is no more.
It exists and it's called now "Wieczorynka", although it's no longer shown by the main public TV channel - from August 2013. They opened a new channel with cartoons for children, which is available countrywide from DVB-T transmitters together with the main channels, so they moved "Wieczorynka" there.
"Wieczorynka", or earlier "Dobranocka" was a 20-25 minute (in the past 10 minute) block of cartoons and other programmes for children shown by the main public TV channel (TVP1) every day at 19:00 (the time was changing throughout the time, sometimes there were single changes due to sports events, but 19:00 was the most typical hour). A custom was also that on weekends they were showing in "Wieczorynka" Disney's series (and, in some periods, the Smurfs - but there was still one day of the weekend, usually Sunday, with Disney).
It has been shown since the 1950's.
And yes, there was a... stereotype? custom? Anyway, it was usually said to children, that they should go sleeping after "Wieczorynka"/"Dobranocka". Who obeyed that, and who not, it depended only on the parents, the child and the discipline in the house. Also on the age of the child.