IMAGINE! It's 5 AM in the morning... you can smell something burning... you realize that the house is on fire... what do you do? Will you evacuate the house and leave your family to burn?
No! You will do anything to wake them up & take them with you!
So how can you know about the blazing hell fire, wake up for Fajr Salaah (prayer) but don't bother waking up your siblings and parents?? #Think? Act!
"O you who have believed, protect yourselves and your families from a Fire whose fuel is people and stones, over which are [appointed] angels, harsh and severe; they do not disobey Allah in what He commands them but do what they are commanded." - Qur'an 66:6 -