  The existence of fourth family follows from the basics of the Standard Model.
Because of the high masses of the fourth family quarks, their anomalous decays
could be dominant, if certain criteria are met. This will drastically change
the search strategy at hadron colliders. We show that the fourth SM family down
quarks with masses up to 400-450 GeV can be observed (or excluded) via
anomalous decays by Tevatron before the LHC.
