When Kathie and Brian go on an 'adults-only' vacation with Heather’s brother and sister-in-law, Heather and Lori are left to fill their shoes at work and take care of Heather’s 4-year-old niece and 7-year-old nephew.  While struggling to entertain the insatiable youngsters, Heather and Lori face an equally huge challenge when they learn a major grocery chain is threatening their hold on their new dream retail location in an upscale shopping mall.  Meanwhile, Heather trains for – and participates in – her first triathlon.