My Kitten/Horse

In general life, Beth most closely resembles a kitten - very cuddly, tiny little cries, just very cute and adorable. When it comes to eating, however, she is a horse. Case in point: born 18 days ago at 5 lbs. 14 oz., 17 1/2 inches. 2-week check-up today weighed in at 7 lbs. 1.75 oz., 20 1/2 inches. Normally they are just hoping to have the kid back at birthweight by the 2-week. So I ask, do I have a kitten or a horse?