The short answer for a single Senegal
A Senegal parrot does not need another bird in the cage to be content. In the wild Senegals move in small groups, but a pet Senegal usually redirects that social drive toward its household. One bird that gets daily handling, conversation, training games, and time out near family activity will often be calmer and more closely bonded than a bird left to entertain itself with a cage mate it never chose. The question is not whether Senegals are social — they are — but whether your time can honestly meet that social need.
When a solo Senegal starts to struggle
Watch the pattern across the whole day, not one noisy morning. A lonely Senegal may contact-call repeatedly when you leave the room, lose interest in toys, sleep more, or begin feather chewing. Those changes can also follow a moved cage, a new work schedule, or less sleep, so note what changed before you assume a second bird is the fix. If the calls happen mainly during hours when the house is empty, the gap is coverage, not necessarily a missing flock mate.
Why adding a second bird can backfire
Two Senegals are two personalities, not a matched set. A newcomer may be chased from perches, have toes nipped through bars, or compete for your attention so loudly that both birds become harder to live with. Separate cages, separate out-of-cage sessions at first, and a quarantine period away from your resident bird are the minimum if you do add one. Even then, there is no promise they will preen, play, or settle side by side. Buy a second bird only because you want that bird for its own sake.
What to try before you decide
Build a week that proves the point either way. Give your Senegal a morning training session, a foraging toy that takes real work to empty, midday company near household activity, and an evening wind-down in the same room as people. Rotate who offers treats and target training so the bird is not dependent on a single person. If behaviour steadies and the bird plays independently between visits, a solo setup with strong human contact is working. If distress persists despite that effort, talk through companion options with an avian vet who knows Senegals.
A practical test is to film a normal workday, with the owner's permission routines unchanged, and watch how the Senegal spends the empty hours. A bird that forages, naps, bathes, and plays in bursts is coping well alone. A bird that sits at the cage door calling in long, unbroken stretches is showing you a gap that toys alone have not filled, and that footage is far more useful for deciding than a single breeder's opinion about pairs.
Making solo life work long term
Keep the cage where life happens without being in constant traffic, protect a long quiet sleep period in a darkened space, and refresh toys before boredom sets in rather than after. Note favourite foods and call patterns as you learn them, so what steadies the bird is written down rather than held in one person's memory. Even when its favourite person is out, the relatives you pick can look at the Senegal's profile through Family Sharing in KinsLe, once you have given them access to it.