sunshinesupermum - okay, so in your family your nana, uncle or other family who fancied a go got to do Father Christmas with you and your siblings in November, December or January, and it was fine, everyone was happy. However the “Universal Father Christmas Christmas” is remarkably consistent in a few elements, one of which is it occurs on Christmas Eve, except in extreme circumstances when he makes a special journey. This is reinforced in films, adverts, books, poems, schools. Despite your experience, in 49 years I’ve only known parents or primary carers (who could be grandparents of course) perform that role, and it is very commonly talked about as being such a short and precious time when it is still “magic”. Many people say that Christmas is never the same after you stop believing yourself until you have young children. Mine are well past that age but the memories for all of us are really sweet. I miss that, and if I have grandchildren I know my daughter, will be looking forward to doing her own traditions around it. Love me though she does, if I did my own version with her children without asking her, I’ve no doubt she’d ask me what the fuck I thought I was doing. Luckily I wouldn’t dream of it. I had my turn.
Also I remember the doubts I had when I got to around 6 or 7 because some school friends’ stocking presents were wrapped and mine weren’t, only those under the tree from people were wrapped. One girl’s stocking had wrapped presents that weren’t even from Father Christmas, they were from her family with labels! My mum managed to feed me some cover story and I hung on until I was 8, but Father Christmas popping into multiple houses for the same child in different months is a bit of a stretch beyond the age of about 3 or 4 I reckon.
Buying grandchildren gifts is (usually) lovely, redoing the whole Father Christmas thing in January without a peep to the parents is not normal.