Disclaimer: 'Mutant X' and its characters = Not mine. (And I'm not overly happy about that!) Lexi and Izzy = Mine.

Author's Note: Thanks for all the reviews, I'll try to keep the updates coming as fast as I can.

Words in / / = Thoughts.

Chapter 1.

The same time.

"Grandpa and Other Grandpa are a'ways fightin'!" Lexi complained, stuffing an impossibly large chunk of birthday cake into her small rosebud mouth and spreading cream and icing all over her face.

"Yes." Izzy nodded emphatically. "Dey vewy silly."

"Why you t'ink dey fight?" Lexi licked each of her chubby fingers carefully, making sure that she didn't miss any of the sugar.

Izzy rested her chin in her cupped hands for a minute, carefully pondering the question. "I t'ink dat Other Grandpa no like Grandpa 'cos Grandpa is more pretty dan him. An' you an' me an' Mommy lib wif Grandpa. Other Grandpa was mean to Mommy w'en she was little." The three year old added indignantly, a scowl on her pretty face.

"How you know Other Grandpa was mean?" Lexi asked curiously. "He nice now."

"Mommy hab bad dweam las' week. I saw it." Izzy explained, before continuing to expand on her theory. "Grandpa was nice to Mommy w'en she was little so she like him more. Dat why Other Grandpa no like Grandpa. He jeawous!"

Lexi nodded, accepting the logic in her sister's argument. "But why Grandpa no like Other Grandpa?" She asked, not entirely satisfied with Izzy's explanation.

Izzy shrugged. "Maybe 'cos he smell funny."

"Yes." Lexi assented, nodding sagely. "An' he sing bad."

Izzy sighed. "Me no like dem fighting. An' Mommy no like it eivver. Mommy wan' dem to stop. We hafta make dem stop."

Lexi sighed, as if weighed down by all the cares and woes of the world. "it not faiw!" She complained. "We hafta do ev'ry't'ing 'round hewe!"

* * *

"Grandpa?"

The timely arrival of the twins halted the hostilities between their grandfathers before they resorted to fisticuffs.

"What can I do for you, Izzy?" Nicholas smiled down at the little girl, who stuck her tongue out at him and kicked him in the shins.

"Me Lexi!"

Rubbing his injured shin, Nicholas glared down at his granddaughter. "Why you little . . .!"

"The girls are a little sensitive about their names. They don't like being mixed up." Adam, who could barely suppress the laughter burbling inside him, informed the other man. "You'd think that after three years, you'd be able to tell them apart by now." He added insultingly.

Ignoring him, Nicholas continued to glare at Lexi. "That was a very nasty thing to do, Lexi." He scolded. "Didn't anyone ever tell you it's not nice to kick?"

Lexi just smiled, not bothered in the least. "It funny."

Adam couldn't control himself any longer. He burst out laughing.

"See." The toddler pointed at him. "Grandpa t'ink it funny."

Nicholas, clinging desperately to the tattered remains of what had once been his dignity, drew himself to his full height and tried to look as intimidating as possible. "If your mother had behaved like that when she was a little girl, I would have put her over my knee. Do you know why?"

"Why?" Lexi asked, mildly curious and not frightened in the least.

"To give her a spanking." Nicholas tried to sound as ominous and impressive as possible. Needless to say, he failed miserably.

"What dat?" Izzy's curiosity was piqued by the unfamiliar term.

Adam leaned forward and explained it to them in a hushed voice.

Identical expressions of outrage appeared on their small faces.

Before anyone could stop her, Izzy charged forward and landed a solid kick to her biological grandfather's left shin.

"Dat mean!"

Before poor Nicholas had recovered, Lexi followed her twin's example and took out his right shin, leaving him to fall with a heavy thud.

"Why I oughta . . ."

"'f you twy to 'pank us, we shock." Lexi threatened, a glowing blue ball of electricity forming in her small hand.

"Yeah." Izzy formed her own ball of electricity and waved it threateningly in Nicholas's direction. "An' Mommy an' Daddy will till you w'en dey get home."

Knowing that this was probably true and more than a little unnerved by the sight of his three year old granddaughters wielding their potentially lethal energy balls, Nicholas gave up the argument and turned to Adam, whose sides were splitting with laughter, with a glare.

"You know, you're not helping here."

"I know." Adam responded cheerfully. "And I have no intention of doing so."

"I think that you're enjoying this!" Nicholas said accusingly.

Adam feigned shock. "No!" His voice was heavily laced with sarcasm. "What tipped you off?"

"Grandpa?" Izzy interrupted before they had a chance to throttle each other.

"Yes, Izzy?"

"Tan Lexi an' me hab some tandy?"

"No." Nicholas cut in before Adam could answer. "Naughty little girls who kick their grandfather don't get candy."

"Izzy no as' you." Lexi told him impertinently, making a face at him and then dismissing him with a wave. "An' you not Grandpa, you Other Grandpa. So," She turned to Adam with an expectant smile. "Tan me an' Izzy hab tandy?"

Unable to resist the temptation to make the other man out to be the 'bad guy', Adam nodded.

"Come on." He scooped the twins up, one in each arm and carried them out of the room. "Let's see what we can find in the kitchen."

As soon as they turned to leave the room, the twins simultaneously stuck their tongues out at a less than amused Nicholas who made a mental note to give his daughter and her husband what he considered to be a long overdue lecture on the proper ways to raise small children.

/They have spoilt those little hellions rotten! If they don't start to teach them some manners now, they'll have finished us all off by their tenth birthday! /

* * *

Ten minutes later.

The Fox-Mulwray sisters sat in their playroom, happily gorging themselves on candy and giggling every time they thought of the expression on 'Other Grandpa's face when they had stuck their tongues out and threatened to shock him.

"Other Grandpa fun to make mad." Lexi pronounced, downing a handful of jelly babies. "He face go all red."

"Yeah." Izzy was more than satisfied with the results of the first phase of her plan. "An' he make a funny noise."

"He near'y much fun as Uncie Jess." Lexi concluded, liberating another handful of sweets from the large bag Adam had given them. She offered them to her sister. "Wan' some?" Izzy shook her head. Lexi crammed the sweets into her mouth. "So, what we doin' now?" Her eyes glittered in anticipation. "Tan we pway wif' dem some mowe?"

"Yes." Izzy assented, nodding solemnly, a slow blooming smile spreading across her angelic face. "We tan."

Their heads together, the twins plotted the next stage of their plan to torment their unsuspecting grandfathers.

TBC.