A/N: This is for lilsherlockain1975's youngest, who was feeling left out. Hope you like it, hon!

"It's not fair."

Molly sighed; once again, five-year-old Davey was pouting over the attention his older brother was receiving. At eleven, Robbie was old enough to go out on cases with Sherlock – nothing higher than a three, of course, and no murders or Molly would hit the roof – and of course anything Robbie could do, Davey wanted to do.

"When you're older, you can go out on cases with your dad, too, love," Molly said (not for the first time). "You know the rules; not until you're ten."

"But I wanna go NOW!" Davey wailed, his blue-green eyes (so like his father's!) filling with tears. Normally Molly wasn't one to give into either son's temper tantrums, but today was his birthday and she couldn't blame him for feeling a bit left out, even if his dad and older brother would be home well before the party started. She held her arms out and Davey crawled onto her lap as if he were still a toddler. She cuddled him close and kissed the top of his curly head (he'd got all his father's features where Robbie looked like a miniature of her, except with his father's lips), and whispered nonsense shushing noises to comfort him.

Sherlock and Robbie came rushing in not fifteen minutes later, both stopping short at the sight of Davey snuffling in Molly's arms. They exchanged glances, and Molly could tell they had both deduced the source of Davey's unhappiness. Ah, she thought fondly, all three of the men in her life shared the same sharp minds; when Davey was old enough, he'd do just as well as his older brother to assist her genius (exasperating!) husband.

"Hey, Davey, guess what!" Robbie said, bouncing over to the sofa where his mum and brother were currently seated.

"What?" Davey asked, not raising his head to look and clutching Molly a bit tighter. Oh, he didn't want to hear how exciting it had been to be out on a case with Sherlock, Robbie knew better! But when she started to give him an admonishing look, Sherlock cleared his throat loudly and shook his head. She subsided, curious, and waited for Robbie to say his piece.

"We didn't solve the case yet," Robbie said in an exaggerated whisper.

That certainly caught Davey's attention; the younger boy peeked up, wide-eyed, staring first at his brother, then his father (who shook his head and scrunched his nose in faux-disappointment), then back to Robbie. "Why not?" he demanded, pushing himself up and sliding off Molly's lap. "Was the bad guy smarter than Daddy?" He sounded incredulous, and Molly bit back a grin at Sherlock's muffled snort of disdain.

"Nope," Robbie said, popping the p exactly as his father tended to do. "We just need a little help, is all. From someone who's an expert in kids."

Davey's face dropped. "Oh, you mean Mum," he said in disappointment.

"Wrong!" Robbie crowed. He poked his little brother in the chest. "We need YOU!"

Oh, the excitement on Davey's face! "Me?" he gasped, once again staring up at his dad. Who nodded solemnly and squatted down. He opened his arms just as Molly had earlier, grunting a bit as Davey hurtled himself at his father. "What do you need, Daddy?"

Sherlock smiled and hugged him tightly. "You, Davey. Just you. Come over to the computer and I'll show you." He stood up, carrying his son, and gave Molly a wink. Robbie hopped over to join them, leaning on Sherlock's shoulder and pointing out the game their father had opened up and was instructing Davey to play. "The clue's in this game, which is made for kids your age. Robbie's too old and I'm hopeless at this sort of thing, so as soon as you solve it, we'll know what the bad guy did with the necklace he stole."

Molly swiped at her eyes; how had she got so lucky, she wondered? How had Sherlock Holmes turned out to be not only a wonderful husband, but an even more wonderful father?

As the three became engrossed in the game Davey was confidently navigating, she decided such a wonderful family deserved an equally wonderful treat. Fairy cakes, she decided, were just the thing. The perfect reward for the gift Sherlock and Robbie had cooked up for Davey's birthday.

SIghing happily, she went into the kitchen and began baking.