Underworld actress Kate Beckinsale showed us that she's very into the holidays this year. She's been celebrating in advance since the beginning of the month, sharing several intimate moments with her 5.1 million Instagram followers. All her posts have one thing in common, though: Willow and Clive, her beloved cats.Kate has a lifelong companion in the felines, and she does everything with them, from dressing up to lighting Christmas trees.Queening TogetherKate poses in a two-piece white midi skirt and crop top alongside Willow as she feels like Queen Elizabeth II. The white blouse, which has a little bow detail at the base with puffy sleeves, adds flair to the outfit, while the simple skirt balances the style. Kate ties her hair up in a messy ponytail and dons silver earrings to compliment her silver sandal heels.On the other hand, Willow wears a frilly barbie pink chiffon sweater with a turtleneck and squats beside her. The cat sits on her lap in a second post, looking menacingly at the camera while the Guilty Party actress looks away. The English actress captions, "On our Queen sh*t," emphasize her mood at the time of the picture and places a Queen Elizabeth caricature on her cat's head.Shopping PartnersFor Kate, shopping is more fun with her cat in a moving cat carrier. She stuns in 6-inch high boots and faux fur coat as she checks a sales rack for Christmas gifts. Beckinsale pairs the coat with skinny black pants and a white crop top, showing her defined mid-riff.Her cat lies in a transparent cat carrier wearing a multi-colored cat dress or sweater (we can't tell from the position.) They seem to be having fun as Kate saunters away like a diva wearing shades at night.Lighting The Christmas TreeKate lights a tall Christmas tree with Clive cheering on from the sidelines. She jokingly captions, "you can take the girl out of London. #TheContours," as she dances to the group's Do You Love Me. Her sense of humor is at an all-time high because she wears their faces on a skirt too!The tree is glowing with bright golden lights and decorations as Kate dances and winds to the music in the background. Her trusted assistant sits there with a cone on his head, watching his mom go off to The Contours.Early Christmas GiftsUntraditionally, Kate opened her cats' Christmas gifts ten days earlier. Wearing an all-black outfit, she tests the tickle remote on Willow and manual massager on Clive. Whereas Willow is more receptive, Clive isn't feeling the cat mom's gift. Perhaps it'll grow on him.In the meantime, have yourself a Merry Christmas like Kate Beckinsale and her pets.