Irish twins are siblings born within the same year. Not the calander year,but in the same 12 months. There called Irish twins because most Irish are Catholic, and Catholics don't believe in birth control, and end up with tons of kids!And us Irish like to get it on...;P
at 4:16 PM on Jul. 18, 2008
Kids that are about 12 months apart or 10 or 11 or 13 months. they call them Irish twins.