It means to grab life with both hands do every great opportunity that comes your way in life some things are yours to be taken
Carpe deum:(English form Latin) Seize the day;, to look introspectively at your self without being distracted by it / to not miss out on today because you are focusing on yesterday.
Enjoy life before it's to late. Because no one knows when there time is up on this earth and obviously your friend and her parents knew this. If you can find a movie called the appointment . This will help explain it better. It is about a reporter that does not believe in heaven but decides to find out after a guy(angel) tells her she has appointment with him next Friday at a certain time because she is going to die then . She does everything she can to accept this is not possibly true and has several close calls including a fire in the building she works in. But when she runs from the building safely she thinks she is okay and everything is just as it was before the guy(angel told her that she was going to die ) as she looks down at her watch she steps backwards into the street and the screen goes dark. This is to show that everyone has a appointed time to die on this world. But where you end up at is your choice. I believe that your friend knew this. What do you believe?
It means to make the most of the day
Live life to the fullest
It means take initiative to ford your own path in life.