It started on his first Christmas alone with Emily. His daughter was always a bright eyed little thing, with dark curls and dark eyes, always smiling and laughing. A ray of sunshine, and some days he desperately needed that. After all of the sadness and death at work, it was nice to be able to come home and see her so alive.
That first Christmas, several years before the divorce. Emily had just turned two a few months ago, and he grinned as she tried to help him decorate the tree. Linda left a week before Christmas, citing family matters necessitating a visit to her sister, and Greg was more than happy to miss out, staying home and decorating, baking cookies, and singing carols. Emily tried to get into everything, and he grinned as he let her 'help' him.
On Christmas Eve, he left her playing in the sitting room for a few minutes before going to get one of her smaller presents, bringing it out and smiling as he watched her eyes light up. "Santa always leaves one present for you to open on Christmas Eve," he said solemnly, watching her tear into the paper and gleefully hold up a new storybook. He ate takeaway, making Emily a hot dog (her favorite food at that point), and he found an old Christmas special that they watched until she fell asleep.
As he was tucking her in, he realized it was one of the best Christmases he had spent in a while. After that, a trend developed.
His wife always had some commitment that would take her away for Christmas, leaving the week before and returning on New Year's Eve. He and Emily spent the holiday together, eating takeaway and watching Christmas films, opening one present on Christmas Eve and the others on Christmas day. Even when she stopped believing in Santa Claus, it didn't dim the fun of the holiday, didn't stop Emily from running into his room early on the morning and jumping on the bed.
For the first two years after the divorce, Linda had kept Emily on Christmas, and his daughter confided that it wasn't as fun. Emily came back the week after Christmas, as he and Linda switched every other weekend and she had taken Emily on the weekend before Christmas. When they got home, they spent the first two days doing all of their traditions. It wasn't perfect, but it worked.
When one of Linda's boyfriends hit Emily, Greg felt no shame at all in calling a number he had memorized long ago, when Emily was still young and Sherlock had only just started working with them. With Mycroft's help, their daughter didn't have to go back to visit with her mother unless she wanted to.
The first Christmas after that was something of a celebration. For the first time in two years, they spent Christmas how they were used to spending it, and they loved it.
When he and Mycroft started dating, however, he hadn't thought about what that would mean for them.
Mycroft usually went to visit his parents for Christmas, sometimes even managing to drag Sherlock along with him. He'd never asked if Greg and Emily wanted to come with him, and neither of them minded. Mr. and Mrs. Holmes approved of them both when they were introduced (Sherlock's fault, but Mycroft would always claim that he had planned to take Greg and Emily out to his parents' house that weekend), and Greg didn't mind sending Mycroft off to his parents' house while he and Emily continued with their tradition.
The second year that they were together, Mycroft asked if they would mind if he celebrated Christmas with them. Emily had told him that he was more than welcome (and, Greg found out later, invited him half a dozen times over the course of the year, and three more times in the weeks leading up to Christmas), Greg telling him to come over on Christmas Eve and be prepared to spend the night. At that point, they were still negotiating their relationship, comfortable with each other and with how things progressed but still willing to take it slow, and Greg saw Christmas as one of their milestones.
When Mycroft turned up, late in the afternoon on Christmas Eve, Emily was making chocolate chip cookies under Greg's watchful eye. Mycroft was roped into the process, unable to say no to the young girl. He ended up getting flour on his waistcoat and had a streak of dough across his cheek from a small dough war initiated by said young girl, but he found that he was enjoying himself immensely.
Mycroft admitted his surprise that Greg didn't cook on Christmas Eve or Christmas Day. He knew that Greg's father had been a chef and had taught both of his sons everything he knew. Greg's elder brother, Bob, was a chef as well and owned his own restaurant, so Greg had been pretty well inundated in the culinary arts.
Greg just laughed and shook his head, Emily grinning as she watched them. "It's tradition," she stated, taking one of the pillows off of the sofa and laying on the floor, looking at the television as the old 'Rudolph' movie played. Emily had a disc with several Christmas films on it, apparently choosing one at random each time the last ended. "We've always done it this way."
Greg told him later about that first Christmas, and how things seemed to just continue on from there, and Mycroft understood. He ate takeaway and watched movies with Greg and Emily, opening his present with a small amount of shock (he hadn't thought they would get him anything, which was foolish because they always did), and the next morning startled awake when Emily landed on the bed.
"It's Christmas," was her only explanation, scampering off the bed and down the hall with Greg chasing her, her shrieks of laughter and his deeper laugh echoing back to where the politician lay, looking at the clock and wondering what gave them the energy to chase each other about, Greg catching Emily and tickling her breathless before going to make drinks for them all.
"Breakfast after presents," he was informed solemnly, taking the cup of tea Emily offered him and watching her drink her hot cocoa, Greg sipping his coffee, both of them nibbling on a cookie. Presents were duly passed out and stockings were raided, and Mycroft was content to sit back and watch.
Emily read one of her new books (one he had gotten her, Mycroft was pleased to note), while Greg made pancakes and bacon. There seemed to be no tradition for this, whatever breakfast the detective had wanted to cook. Emily set the table, tearing herself away from her book briefly before diving back in after breakfast was over, content to curl up in an armchair by the window and read.
Later, she asked him to help her with the small science kit that was one of her presents, supposed to grow crystals. After that (which took less time than he had suspected it would) he and Greg cursed , Emily giggling madly, as they worked to build the Lego set Mycroft had gotten Emily after he learned of her interest in The Hobbit. She fell asleep in the chair she had been reading in, book in the hand that dangled limply off of the chair but held firm in a surprisingly strong grip.
Greg picked her up, Emily still small enough that it wasn't much struggle, and he took her to bed, leaving Mycroft behind to contemplate everything that had happened during the past two days.
"I believe that you were right, Gregory," he said finally, when Greg had come back from settling Emily in bed and had joined him on the sofa. "Some traditions should be kept."
As time went on, they adapted a few things, spending the twenty-third and the twenty-sixth with his parents in lieu of a Christmas Day visit, and Sherlock and John got in the habit of visiting then as well. Their daughter and Emily got along well, even though Emily was several years older. Some traditions never changed, however, and he doubted that they ever would. Some traditions deserved to be kept, and the memories of his first Christmas with the Lestrades (memories of a bright eyed child giggling as she smeared a bit of dough on his cheek 'accidentally', of watching Christmas films with his partner a warm weight at his side and Emily contently stretched out on the floor, of being abruptly woken up by Emily jumping on the bed, of Greg tucking her in that night, and of everything in between) reminded him that those traditions shouldn't be forgotten, regardless of how old they would be and where they would go.