In Astrology we search for significant telltales on a natal chart. The 4th house is where we find clues for father figure, father background and family background. There we an see indication for immigration, education, trauma and so on events and circumstances that were and are involved with the father and the family.
A populated 4th house increases the chances of patriotic activity and an emphasized 11th house shows tribal involvement (community) in one’s life.
for example:
well aspected and strong moon on the 4th house may show a lineage of strong women.
Neptune on the 4th house shows a religious background
Pluto in this position talks about immigration or some other physical transformation that happened to family or father
As for signs of the 4th they don’t tell much but the ruler of 4th house can give us more details about one’s brought up and family background.