The breed's usual attitude to other dogs
Most Boston Terriers are genuinely sociable with other dogs. They were bred as companions rather than for guarding, fighting, or solitary work, and a well-raised Boston typically greets other dogs with play bows, wiggly enthusiasm, and a wish to join in. Many live happily as the second dog in a household and take cues from a calm resident about house rules, walk routes, and when the evening is for sleeping. That breed tendency is a starting point, not a guarantee, because early socialization and individual temperament shape the adult far more than the label on the breed.
Where friction can still appear
A Boston who missed out on puppy socialization, or who was frightened by a larger dog, may bark and lunge on the lead while actually being unsure rather than hostile. Some Bostons, particularly unneutered males living with another male, can turn competitive over food, toys, or a favorite person's lap. Play itself needs watching: Bostons throw themselves into wrestling and chasing, but their short muzzles mean they overheat and run out of air sooner than a long-nosed playmate who wants to keep going. Step in for breaks, offer water, and end games while everyone is still cheerful rather than after someone gets snappy from exhaustion.
Introducing a Boston to a resident dog
Set the first meeting on neutral ground, a quiet street or a park neither dog owns, and walk in parallel at a distance where both stay relaxed before closing the gap. Keep leads slack, let them sniff briefly, then move on together so the walk itself becomes the shared activity. At home, feed separately from the start, pick up high-value chews, and give the new dog a bed and space of his own rather than letting him muscle into the resident's spots. Supervise all together-time for the first weeks, and separate them when you go out until the relationship has a track record.
Living in a multi-dog household
Daily management prevents most problems. Separate feeding stations stop the faster eater from auditing the slower one's bowl, and individual training time keeps a Boston from learning that the other dog's name also means treats. Watch the quiet signals: one dog always yielding toys, avoiding rooms, or eating hurriedly is telling you the balance needs adjusting. On walks, a Boston and a bigger, stronger companion may need different paces and different kit, so the smaller dog is not dragged through the bigger dog's workout. Bostons also copy housemates, for better and worse, which makes a polite resident dog the best teacher a puppy can have.
The verdict for second-dog shoppers
If you already have a sociable dog and want a companion who will actually enjoy his company, a Boston is a strong candidate, provided introductions are staged and resources start out separated. Be more cautious if your resident dog dislikes bouncy, face-to-face play styles, because Boston enthusiasm can offend a reserved dog even when it is friendly. Households that run both dogs' routines deliberately tend to settle fastest, and KinsLe's Care Teams support exactly that by letting you assign each dog's walks, meals, and training tasks to named helpers and see each job marked complete with its time.