A cousin prime is a prime \(p\) such that \(p + 4\) or \(p - 4\) is also prime. Cousin prime pairs: \((3, 7), (7, 11), (13, 17), (19, 23), (37, 41), (43, 47), (67, 71)\).
Like twin primes, it's conjectured that there are infinitely many cousin prime pairs, though this is unproven.