if my cousin has a baby what am i to the baby

If your cousin has a baby, you are the baby's "first cousin once removed." This term means that you and the baby share a common set of grandparents, but you are one generation apart. The phrase "once removed" signifies the difference in generations. Although the technical term is "first cousin once removed," many people informally refer to such children as nieces or nephews, and you might be called their aunt or uncle depending on family preferences.