Quadruplets.
If you mean eight babies born to one mother at the same time, the word is 'octuplets'. There is no specific name for a gathering of eight pairs of twins, if that's what you meant.
quintuplets.
People
What do you call group terms such as swarm and ream?
group of mothers
A group of scholars
A group of ants is called a colony or an army.
A group of warlocks is called a coven as in witches
An octet.
Twins - group - ended in 2008.
Twins - group - was created in 2001.
The Twins - group - was created in 1980.
Quintuplets quintuplets. quin = 5 i believe. like a quintet.
Conjoined twins or siamese twins.
Because the twins are the worst team in baseball.
Conjoined twins.
sextuplets
If it is a group of calves born from different mothers than you call them a herd of calves or a group of calves. If it is two calves born at the same time from the same mother than they are twins, just the same as human offspring would be called.
eight
Dizygotic twins. If they were fertilized in the same egg, they would be called monozygotic twins.