The poster who repeatedly claimed that "Complete Savages" is an imitation of "Quintuplets" needs to get his/her facts straight.
Firstly, the premises of the two shows are not particularly similar. The family in "Quintuplets" is comprised of three sons and two daughters (all of whom obviously are the same age) and their married parents. "Complete Savages" features five sons (all of whom are different ages) and their single father. The only obvious similarity is that both families contain five kids with differing personalities, which is a rather broad concept.
Secondly, both "Quintuplets" and "Complete Savages" entered development in 2003 (as candidates for their respective networks' fall 2004 schedules). The "Complete Savages" pilot was shot on April 20, 2004 -- a mere twenty days after the "Quintuplets" pilot was shot (March 31, 2004) and almost two months before the latter actually aired (June 16, 2004). The early debut of "Quintuplets" was enabled by Fox's decision to rush the series into production.
In other words, even if the two programs were virtually identical, neither could possibly be a "rip-off" of the other.