“Lift up the heads of the children of Gershon them etc...” (Numbers/Bamidbar 4:21-22)
There is a reason why sometimes ״to their families" is written before "to the house of their ancestors", and sometimes "to the house of their ancestors" [before] "to their families." The answer is according to the passage "lift up the heads of the children of israel according to their gilgulotam according to their families etc..."(Bamidbar 1:1). For the tzaddik uplifts the entire world and he lifts them up by means of his devekut and by means of his holiness. By means of this he brings them close to the service of the Creator may his name be blessed. This is called "nesiut rosh"- the uplifting of the head. Therefore HaShem commanded that this uplifting of the head will conduct itself according to the gilgulim/reincarnations. For the tzaddik who knows the reincarnations of souls can know which man has a holy soul or from which world ones soul was taken. Moshe and Aharon were on this level and they knew the reincarnation of the souls. Therefore HaShem may He be blessed commanded "lift up the souls of the children of israel Le gilgulotam- " which means according to the gilgul of the souls-- this is how you should cause them to ascend above.
However, simple person whose souls isn't on that big of a level, they too need to ascend and lift up their heads. Why should they be harmed? And how can they be lifted up? Since they are below, for this reason the tzaddik needs to connect them to the holy ancestors who contain all of Israel. Then they will ascend above by means of the ancestors, and this is why it is written "to the house of their an ancestors" before "to their families" in order to lift them up into the remainder of the families of israel. But for the ones who are tzaddiks whose souls are from the higher world it is the opposite, they raise them according to the order of from below to above - first "to their families" and afterward "to the house of their ancestors" To attach them with the levels of the ancestors as well...