Katherine was probably born in Lambeth in about 1523, but the exact date of her birth is unknown. Soon after the death of her mother (in about 1528), Katherine was sent with some of her siblings to live in the care of her father's stepmother, the Dowager Duchess of Norfolk. The Dowager Duchess presided over large households at Chesworth House in Horsham in Sussex, and at Norfolk House in Lambeth where dozens of attendants, along with her many wards—usually the children of aristocratic but poor relatives—resided. While sending young children to be educated and trained in aristocratic households other than their own was common for centuries among European nobles, supervision at both Chesworth House and Lambeth was apparently lax. The Dowager Duchess was often at Court and seems to have had little direct involvement in the upbringing of her wards and young female attendants. As a result of the Dowager Duchess's lack of discipline, Katherine became influenced by some older girls who allowed men into the sleeping areas at night for entertainment. The girls were entertained with food, wine, and gifts stolen from the kitchens. Katherine was not as well educated as some of Henry's other wives, although, on its own, her ability to read and write was impressive enough at the time. Her character has often been described as vivacious, giggly and brisk, but never scholarly or devout. She displayed great interest in her dance lessons, but would often be distracted during them and make jokes. She also had a nurturing side for animals, particularly dogs. In the Duchess's household at Horsham, in around 1536, Katherine began music lessons with two teachers, one of whom was Henry Mannox. Mannox's exact age is unknown; although it has recently been stated that he was in his late thirties, perhaps 36, at the time, this is not supported by Katherine's biographers. Evidence exists that Mannox was not yet married, which would be highly unusual for someone from his background at the time to have reached mid-thirties without being married - he married sometime in the late 1530s, perhaps 1539, and there is also some evidence that he was of an age with two other men serving in the household, including his cousin Edward Waldegrave (who was in his late teens or early twenties from 1536-8). These pieces of evidence indicate that Mannox too was in his early to mid-twenties in 1538. This is, however, guess work, based on interpreting fragmentary surviving details about Mannox, since there are no baptismal records for him.