Eileen loves Christmas - everything from the Nativity story to that wonderful knowledge you have done all the present shopping and what you've bought for others should go down well. She goes to a crib service at the church which used to be the hall used for Jenny's playgroup and then enjoys ringing Jenny up and seeing how her preparations are going. At this stage Jenny is up to her neck in it (as Eileen well knows) and is aware her mother is having her annual "wind Jenny up a bit" time. Eileen sees it as an enjoyable part of Christmas Eve, Jenny sees it as some kind of penance.
Eileen has absolutely no time for any of these and the only thing stopping her inflicting some kind of permanent silence spell on the lot of them is Jenny pointing out that it would alert people to the presence of magic on earth. It would be the only thing to explain the sudden absence of dreadful, tacky boy bands. If it had not been for that, Eileen would've happily whipped her wand out here (and Jenny would've joined in. She can see the point of magic if it gets rid of life's irritations).