Thompson Family Christmas, Queen Elizabeth Hall, London

As "Winter Wonderland" inches to a chaotic close, the most striking image is that of stern folk veteran Bob Davenport sharing a mike with skittish transvestite diva Justin Bond. One of many memorable sights for people to take with them and one that sums up the evening's unlikely culture clash.

Teddy Thompson, scion of a musical clan that includes Fairport Convention founder Richard and his former wife Linda, though he struggles to ignite his own career, remains well connected; especially with US equivalents the McGarrigle-Wainwrights. Their annual Christmas soiree in New York, a mix of ancient carols and modern ditties, provides Teddy with the template for this Amnesty benefit. Diffident and bumbling, he lacks Rufus Wainwright's assurance and dramatic sensibility, not to mention Lou Reed and Emmylou Harris on speed dial, but this more British, homespun affair comes with its own transatlantic charm.

Much of that is due to the Thompsons' own involved, tempestuous family history. You wonder if Teddy should invest in a relationship counsellor along with a musical director, yet Richard and Linda edge around each other, the former seated with the band and his ex-missus in the chorus. It's a low-key way, then, of performing together for the first time since the early Eighties. For their turns, Richard swans in with a witty festive number he wrote on the flight over from Los Angeles, while Linda, notoriously shy, sings off stage, an effort that reduces her son to tears.

Elsewhere, folk provides the most beguiling moments of the evening. A while has passed since traditional music formed the genre of choice for political activists (think Dylan and Baez singing "We Shall Overcome") and only the septuagenarian Davenport reminds us of this heritage as he fiercely declaims William Blake's "Holy Thursday". More insistent are reminders of the pagan roots of many Christmas traditions – notably "The Holly and the Ivy" as performed by the Thompsons and Kathryn Williams. Bert Jansch, meanwhile, pays apt tribute to the recently departed Davey Graham with a liquid version of his groundbreaking instrumental "Angi".

In the New York lounge contingent, Bond winningly vamps his way through "Have Yourself a Merry Little Christmas". More prosaic fare comes from Teddy's sister Kamila.

Maybe, given tonight's theme, Teddy wants us all to ponder our place in the human family. This could certainly be a Yuletide tradition worth keeping.