"...Well most people here believe that life is predestined so why would they stop smoking around their children? .."
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I would like to mention the islamic view on predestination:

One day the Messenger of Allah (saws) noticed a ‘bedouin’ (desert Arab) leaving his camel without tying it and he asked the ‘bedouin’: "Why don't you tie down your camel?" The ‘bedouin’ answered, "I put my trust in Allah." The Prophet (saws) then said, "Tie your camel first, then put your trust in Allah"

Related by At-Tirmidhi.

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So when a person beleives in predestination it does not mean that he will not do what he is supposed to do. (however what is predestined will happen)