The Brendan O'Carroll comedy's first seasonal instalment 'Buckin' Mammy' aired to an audience of 9.4m (35.5%) at 9.30pm, according to initial overnight data.
Matt Smith's farewell to Doctor Who - and Peter Capaldi's official debut as The Doctor - was seen by an average audience of 8.29m (30.7%) at 7.30pm. Audience figures peaked at 10.2m as Smith's Doctor regenerated.
Rufus Hound's Strictly Come Dancing victory aired to 7.3m (35.4%) at 5pm, and Call the Midwife's Christmas special picked up an audience of 7.08m (30.1%) at 6.15pm.
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Elsewhere on the channel, Janine Butcher's comeuppance on EastEnders was witnessed by 7.78m (29%) at 8.30pm, with a further 599k (3.2%) watching the 10.30pm repeat on BBC Three.
However, Coronation Street's hour-long special aired to 7.91m (29.4%) at 7.30pm (+1: 360k), as Roy's hopes for a quiet day with Hayley were dashed and the Platts experienced a nightmare Christmas.
Rokhsaneh Gwaham-Shahidi's surprise return to Emmerdale as Leyla Harding was seen by 5.5m (23.6%) at 6.15pm (+1: 253k).
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Downton Abbey was ITV's highest-rated programme in primetime outside of soaps, airing to 6.59m (25.3%) at 8.30pm. A further 420k (2%) tuned in later on +1.
Paul O'Grady's For the Love of Dogs Christmas special was seen by 3.9m (18.5%, +1: 412k).
BBC Two's highest rated primetime shows were Morecambe and Wise: Leading Ladies, airing to 2.04m (7.6%) at 8.30pm, and Mark Gatiss's adaptation of The Tractate Middoth, which chilled 1.23m (4.6%) at 9.30pm.
Channel 4's most-watched programme in primetime was Bear's Wild Weekend with Stephen Fry, seen by 1.99m (7.4%) at 8.30pm. Meanwhile, Michael Jackson's This is It led Channel 5's primetime schedule with 988.8k (4.8%) at 9.30pm.
The most-watched film on Christmas Day was Toy Story 3, airing to 6.32m on BBC One at 3.20pm.
Finally, 5.68m tuned in for the Queen's annual Christmas message at 3pm on BBC One, with a further 1.83m watching on ITV at the same time. Edward Snowden's Alternative Christmas Message for Channel 4 aired to 600k on initial broadcast at 4.15pm.
BARB ratings data supplied by Attentional