Sophie Turner is back on mommy duty just in time for the holidays ... it's her turn to look after her two children as part of her child custody arrangement with Joe Jonas ... but a family reunion may be in the cards.
According to new legal docs, obtained by TMZ, Sophie's got the kids through Jan. 7 ... which means she'll probably be celebrating Christmas and New Year's with Willa and Delphine over in London.
But, get this ... Joe is in England too -- he was recently spotted at London hot spot Chiltern Firehouse -- so it appears there's at least a decent chance Joe will get to see the kiddos on Xmas too.
Of course, the big question then becomes ... will Sophie and Joe spend time together with their daughters for the holidays, which are traditionally a family affair?
The girls have been with Sophie since Dec. 16 ... and they're allowed to travel with her in the United States and the United Kingdom ... but the kids have to be dropped back off to Joe in NYC on Jan. 7.
Remember ... Joe had the kids for Halloween and Thanksgiving, so the parents are splitting holiday duties under their temporary child custody agreement as they work through a divorce.
Meanwhile, Sophie was spotted making out with British aristocrat Peregrine Pearson earlier this month in London ... before she had the kids.
The best thing about divorce ... two Christmases!!!