13 Lots were cast for each gate, according to their families, young and old alike.

Read 1 Chronicles 26:13 Using Other Translations

And they cast lots, as well the small as the great, according to the house of their fathers, for every gate.
And they cast lots by fathers' houses, small and great alike, for their gates.
They were assigned by families for guard duty at the various gates, without regard to age or training, for it was all decided by means of sacred lots.