Video above: Fiona’s greatest hits: 3 years of sassy hippo blissThey grow up so fast. Fiona the hippo has reached a major milestone.Weighing only 29 pounds at birth — 25 pounds lighter than the lowest recorded birth weight for this species — the portly princess now weighs a whopping 1,500 pounds, Cincinnati Zoo officials said Friday. That’s consistent with a normal hippo her age. She’s