A dog who steals the duvet is usually building a bed, not sending a distress signal. Heaping bedding up, turning circles on it, scrabbling with front paws, and tunnelling down into the pile all descend from wild ancestors trampling grass and leaf litter into a sleeping hollow. A dog who does that work, curls tightly into the result, and stays asleep until morning has normally made herself an excellent nest. The behaviour itself tells you very little; what follows it tells you almost everything.
Reading the Whole Night, Not Just the Nesting
A comfortable nester follows a clear arc: rearrange, circle, settle, sigh, sleep. She may rebuild the nest once if she gets warm or a cover slips, then she is out for the night. Her body is loose, her breathing slows, and she wakes in the morning in roughly the shape she fell asleep in. An anxious dog's night looks different in specific ways. She nests but cannot stay nested: up and down repeatedly, rebuilding the pile, panting with her mouth open in a cool room, pacing to the door and back, whining softly, or pressing against you and still failing to settle. Look also at the hours around bedtime: a dog who has started resisting going to bed, who drools or licks her lips as the house quiets, or who wakes the household at the same unsettled hour night after night is giving you information the nesting alone was not.
Changes That Deserve a Vet Visit
Nesting that is new, suddenly intense, or paired with other changes should not be waved away as a quirk. Restlessness at night is a common early sign of pain, because lying still lets sore joints and aching teeth make themselves known, and older dogs in particular may pace and resettle as they try to get comfortable. Changed drinking, changed appetite, weight change, or new night-time toileting alongside the restlessness all strengthen the case for a vet check. Mention the pattern precisely: when it started, how many times she gets up, and whether she ever truly settles. Also check the simple physical causes first. A warm room, a heavy winter duvet, or a bed that has migrated next to a radiator will produce a dog who digs covers off and rearranges them all night in search of a cool patch. So will an under-exercised day. Rule those out before worrying, because a comfortable dog in a hot room looks remarkably like a restless one.
Give Her a Legal Nest
Whatever the cause, your bedding survives better when she owns a sanctioned alternative. Set up a bed beside yours with two or three loose blankets that are entirely hers to excavate, and praise her for digging into those. Many inveterate nesters prefer a pile they can burrow under to any structured bed, so offer both a base cushion and a heap. If she migrates back to your covers, calmly trade: lift her blankets into an inviting mound and let her discover them, rather than staging a nightly tug of war over the duvet. Keep a brief note of her nights for a couple of weeks if you are unsure which picture fits: settled after nesting, or restless throughout. Wash her blankets on a rotation, one at a time, so the nest always smells like her rather than like fresh laundry. For the nights that fit neither picture cleanly, put a follow-up question to KinsLe's Kimmy; she answers using the KinsLe Answers library.