No, not a round-number birthday like 20 or 30 (must be careful here). Not the day when her ever-loving and devoted husband eventually gets round to taking her out for dinner without being plaintively hinted at or otherwise cajoled.
Nor indeed the day when the younger Dixons miraculously acquire the skills to cook their own meals and wash their own clothes, leaving their Mum to pursue the glittering showbiz career she denied herself to minister to their needs when they were babes in arms.
No, it's none of these things. Sunday is Weston Village Open Gardens day, and for the past six weeks Mrs D – along with the proprietors of eight other venues around the village – has been buffing up the begonias and organising tea rotas in preparation for her (and indeed our) role in this annual event, which raises funds for Dorothy House and for local voluntary groups.
The horticultural details are a little sketchy to this reporter, whose only endeavours in the field of cultivation lie in turning chilli seeds into insect-riddled twigs. But the disruption to the normally gentle flow of family life is plain to anyone who walks into the house.
First, the cat. Resident feline must be caught and groomed in order to present attractive appearance to paying visitors.
Cat does not mind being caught, and rather fancies the idea of chatting flirtatiously to a series of paying visitors who are as yet unaware of its essentially vicious nature; but objects vociferously and violently to application of comb to fluffy undercarriage. Normal fluff disposal, believes cat, is done by self-grooming and subsequent chucking up on sitting room mat.
Grooming operative (your humble columnist) dons thick leather gauntlets, manhandles cat to bottom of garden and makes with the comb.
Cat calls at top of voice to RSPCA, Cats Protection League, Blue Cross and everyone else in a 500-metre radius, pierces gloves with fangs and claws, and runs for cover under bush.
Cat 1, Columnist 0.
Next, the guinea pigs. Each, it has been decreed, must be individually photographed and labels made up so that the aforementioned paying visitors can identify which is which.
(Luckily, same idea does not apply to the plants, or we'd be here till Christmas. Mrs D is supposed to remember what they are, although she looks doubtful when asked about the botanical credentials of that big green one with all the leaves on it.)
Guinea pigs decline offer of free publicity and lurk under straw in darkest recesses of hutch. Paparazzi- style doorstepping brings unsatisfactory results: all pictures are identical, with cavy red-eye suggesting quite convincingly that the three fluffy creatures are actually the spawn of hell.
Finally, the family. Staff briefing at 10:00 hours sharp. Dixon Junior and Pa, one step forward. Man the gate, take money, repel boarders. Excellent maths revision opportunity for one. Excellent sunburn-on-bald-patch opportunity for other. Because it's bound to be warm and sunny.
Whatever the weather, Weston Village Open Garden Event runs from 1pm to 5pm on Sunday, June 4. Please come along: it's in a very good cause and it's a jolly afternoon out.