The A Word, writer Peter Bowker’s beloved BBC series about a family adjusting to the autism diagnosis of a son called Joe, was never content with just being TV’s best appraisal of that condition. It was always looking beyond, not only at the child and his parents but also at uncles, aunts, grandparents and friends, all of them affected but not defined by having autism in their lives. By the end of series three, that extended family was so well established that the wedding of Joe’s grandfather’s partner’s son, Ralph, was a significant event. Ralph and his wife now get their own spin-off, Ralph & Katie (BBC One), the arrival of which demonstrates that Bowker is looking forward again, determined to use the goodwill around The A Word to its fullest. As well as focusing his new show on two characters and actors (Leon Harrop and Sarah Gordy) who have Down’s syndrome, Bowker has handed most of the scripting duties over to writers with disabilities. Alongside director Jordan Hogg, who has cerebral palsy, numerous crew members with disabilities were also hired, many as trainees. Just as Ralph & Katie expands The A Word’s gang by introducing new characters, Bowker’s quest to make television more inclusive is moving onwards at admirable speed. When we last saw them, Ralph and Katie were being helped into their new house by Ralph’s stepdad, Maurice (Christopher Eccleston). Ralph had told Maurice he was “better than” his biological father who hadn’t been able to face raising him – a moment to make a nation’s tear ducts run over. Initially there’s no sign of Maurice, and that dynamic is a big loss. But Ralph, like the new show built around him, needs to strike out alone. It seems he will be coping without Maurice for a while: “He’s trekking in Nepal,” reports Louise (Pooky Quesnel), Maurice’s other half and Ralph’s brusquely doting mother, who does cross over from the cast of the The A Word. “He’d run out of people to annoy in Cumbria.” Ralph’s replacement foil is Danny (Dylan Brady), a new support worker for Ralph and Katie who is younger – and looser in his approach to care work – than Louise would like. Ralph remembers Danny as the cool kid from school. Danny wants to atone for having witnessed Ralph being bullied by their classmates and doing nothing to stop it. Hostility from outsiders is one obvious source of drama, but the opening two episodes of Ralph & Katie take the more interesting approach of generating conflict from within. Ralph is not some passive avatar around whom things happen: his problems, early in his marriage, are of his own making. In episode one he bridles at Katie allowing her co-worker Emma (Jamie Marie Leary) to stay in the marital home while she recovers from a breakup, and ends up saying something hurtful about Katie’s standing in the workplace. In the second instalment, further doubts cloud Ralph’s mind when Katie receives an anonymous card in the runup to a big Valentine’s Day fundraiser for the local choir. This insight into the emotional lives of people for whom judging social situations and articulating feelings can be difficult is valuable, and forms the crucial fleck of grit in what is mostly a much gentler show than the already pretty cosy A Word. At times Ralph & Katie leans towards tweeness: Craig Cash ladles on the singsong eccentricity as the couple’s sticky-beaked neighbour Brian, and the mystery-Valentine storyline is not the only one that is a little too worn. But there is real joy and comfort in re-entering the A Word world, a beautiful place – we feel as if we’re on holiday in the fabulous Lake District – powered, even more explicitly now, by kindness and tolerance. More importantly, Ralph & Katie isn’t just good-humoured, it is funny. In its best moments it recalls a bygone era of soaps, Coronation Street in particular, before they became overrun with adulterers, murderers and cast-obliterating catastrophes, when they were adept at character-comedy based on low-stakes community events. That requires not just skilful writing but fine comic acting, and Harrop has the necessary talent. Bowker and his team have a cheat code when penning comedy scenes: just put “Ralph looks at him/her” in the script and let Harrop get a laugh with an expertly timed eyebrow lift, side-eyed glance or bullshit-detecting stare. Opposite him, Gordy has the thankless role of the older, more serious Katie, who also had far fewer appearances in The A Word to establish herself. She does well to bring through Katie’s essential sparky optimism. Ralph & Katie may not be fully in its groove yet, as evidenced by the on-screen captions archly punctuating the action, which are the sort of awkward, try-hard innovation you can imagine being dropped in a more assured second season. But there is easily enough here for it to keep stepping forward with confidence.