Well you should get enough sleep when you wake up alone feeling that you had enough ... there is no law and limitation for sleep.... to sleep is to rest ...

6 Feb 2012 ... While up to 15 hours is ideal, most infants up to 11 months old get only about 12 hours sleep. Establishing healthy sleep habits is a primary ...

My mom says that no matter how much a teenager sleeps, they will ALWAYS be tired. She says that cause when my mom asks a teenager "how are you?