Rating Newest Oldest. Best Answer: It is important because thanks to your family tree you get to know who your relatives are or were..They are your roots and it is important and nice to know them, plus a lot of fun..They are all part of your extended family in time.Source(s): Joe Z Â· 8 years ago.ating Newest Oldest. Best Answer: It is important because thanks to your family tree you get to know who your relatives are or were..They are your roots and it is important and nice to know them, plus a lot of fun..They are all part of your extended family in time. Source(s): Joe Z Â· 8 years ago.