A den stocked with the family's scent
Follow her logic and the hoard makes sense. A child's soft toy is light enough to carry without effort, squashes comfortably under a chin and carries the strongest possible smell of a small person she adores, mixed with the scents of the child's bed and play areas. Her own bed is her safest place. Moving treasured, family-scented objects into it, one deliberate trip at a time, builds a nest that smells like the whole household gathered around her while she rests. Many dogs do a milder version with shoes or socks; soft toys are simply the perfect material, and a dog who has discovered them rarely settles for less appealing loot.
Why one by one, all day long
The steady shuttle trips are part of the reward. Collecting gives her a job with a clear beginning and end: spot a toy left on the floor or a sofa, carry it carefully, arrange it in the bed, return for the next. Dogs who enjoy retrieving and carrying often find the transport itself satisfying, separate from owning the pile. She may also have learned that a raided toy brings a child to her bed for a gentle negotiation, which adds pleasant social contact to each acquisition. Timing can matter too: dogs who feel a strong urge to gather and nestle soft objects sometimes do so in waves across the day, resting among the collection between expeditions, which matches the unhurried pattern you describe.
Swapping fairly so children keep their favourites
Confiscation battles teach her to grab and run, so trade instead. Keep two or three dog-safe soft toys that are hers, rotate them so they stay interesting, and each time she takes a child's toy, offer hers in a friendly swap, then return the rescued toy to the child out of her sight. Put a simple rule in place for the children: favourite toys sleep on beds or shelves, not on the floor, because floor toys are fair game in dog law. Praise her for carrying her own toy to her bed as enthusiastically as you can, so the approved version of the game pays best. If she guards the pile, do not reach in; call her away happily and trade from a distance. Wash her own soft toys regularly and rotate them back smelling clean but familiar, as a freshly returned favourite often holds her interest longer than a brand new toy she has not claimed yet.
When hoarding is more than collecting
Most toy hoarding is harmless comfort behaviour, but watch for changes that suggest something else is driving it. A dog who suddenly becomes restless, carries toys while whining, tries to nurse them, loses appetite or guards the bed fiercely has moved beyond cheerful collecting, and those shifts deserve a vet conversation because body and mood changes can sit behind nesting behaviour. Also step in if she starts shredding and swallowing fabric or stuffing, which turns a sweet habit into a safety issue. Note when the change began and what else shifted with it. KinsLe keeps the household aligned on this, since Family Sharing puts her profile, her swap routine and notes about any change in the hoarding in front of every family member who cares for her.