The short answer: yes, if the size gap is managed
Papillons were bred as companion spaniels, and it shows in their social life. Most are bright, playful and genuinely interested in other dogs, and a Papillon who grows up with a housemate often treats that dog as a playmate, a warm sleeping companion and a partner in patrolling the house. Temperament is rarely the obstacle in a multi-dog home. Physics is. A Papillon's fine bones and low-slung body sit at exactly the height where a large dog's playful swipe, a bouncing adolescent landing badly, or a pile-up on the stairs can break a leg or worse. Judge the match by the other dog's body and manners, not by how friendly everyone seems on day one.
The temperament you are adding to the pack
Despite the delicate silhouette, a Papillon is not a shrinking ornament. This is a confident, athletic toy breed that learns quickly, enjoys training games and can be surprisingly assertive with dogs many times its size. That boldness is mostly charming, but it means a Papillon may square up to a large dog who would rather be left alone, and it will not always back down first. Papillons also bond intensely with their people, so a new Papillon in an established pack needs its own share of lap time and one-to-one attention, or it can turn noisy and demanding to win a place in the queue.
Matching the housemates
The safest companions are dogs with a soft, measured play style: a gentle older dog, a calm small or medium breed, or another Papillon. A big dog can work beautifully if it is the placid, self-controlled type who steps around small animals rather than through them. Be cautious with boisterous young dogs of any size whose play involves body-slamming and wrestling, and with breeds that chase and grab small fast-moving animals, since a running Papillon can look like prey at a glance. Introductions should happen on neutral ground, on leads, with the small dog free to retreat rather than being held in someone's arms, which tends to make toy dogs more reactive, not less.
Running a mixed-size household
Feed the Papillon separately, somewhere it can eat slowly without a larger dog hovering; size differences turn food competition into a real risk rather than a squabble. Give the Papillon its own route up and down from sofas and beds, ideally steps or a ramp, and block unsupervised stair races while a young housemate is still clumsy. Watch play for the warning signs that the small dog has had enough: lip licking, freezing, snapping at a dog it normally likes. If a Papillon ever comes up lame after a collision, is holding a leg off the ground, or cries out when picked up, that is a same-day veterinary visit, because fractures in toy breeds are easy to miss and slow to forgive delay.
Keeping every dog's routine straight
A multi-dog home runs on small, repeated acts of management, and they are easy to drop when several people share the work. KinsLe's Care Teams let you assign each dog's duties — who feeds the Papillon in its quiet corner, who supervises the evening play session, who checks that the gate is closed — and completed tasks are marked with a timestamp, so nothing about the smallest dog's day depends on memory or guesswork.