Courtesy: Raymond Flores

When Isabelle Busath and Isabella Thordsen of Citrus Heights, Calif., add another rule to their spiral-bound notebook, they should make sure it includes allowing their mothers to go online whenever they want.

That is exactly how the two young cousins, ages 10 and 8 respectively, came to be reunited with their rules book accidentally left behind at their local Walmart store last Friday.

The book, discovered by a 20-year-old Walmart employee, Raymond Flores, became an Internet sensation after Flores contacted the media to try to find its owner and its touching rules - including the rules "Don't bite the dentist" and "If you're going to wet your bed, wear a pull-up" - went viral.

Click HERE to read more about the rules book and Flores.

On Wednesday, Isabelle's mom, Michelle Busath, saw an article online about a rules book written by kids. Thinking that it was perhaps a new trend that her daughter was part of, Busath clicked on the article. When she saw the article's mention of the "Don't bite the dentist" rule, she realized this was the same rules book her daughter and Isabella had lost.

Busath emailed the news station, a local FOX affiliate, and last night the two young girls were reunited with their rules book and got to thank Flores for going the extra mile to make sure it ended up back in their hands.

"I was really shocked that someone would even keep a little book like that in the first place," Busath said of Flores, who has said he was motivated by rule number 154,"Protect this book." "That he cared enough to find the owner for it, that shows a lot about him too."

"She was of course ecstatic," Isabella's mom, Sarah Tatarakis, told ABCNews.com of her daughter's reaction. "They already had other rules in mind and were writing them on paper last night while waiting to get their book back."

The girls, according to their mothers, are both avid writers who created the book over Christmas break in an attempt to teach Isabelle's 6-year-old sister about rules. Their moms knew about the book and how much it meant to them but, like a diary, its contents were kept private between the girls.

Now that the book's rules have become so famous, the girls did allow for one exception to their privacy rule. They let Flores add a rule to the book last night. He wrote, "Stay in school," according to Busath.

Both moms say they are overwhelmed by the worldwide attention their daughters' feel-good story has received. Tatarakis, who is holding on to the book for safekeeping, says she is also putting it to good use.

"I was trying to get her [Isabella] to go to bed last night and she was so excited she wanted to stay up and was pleading ," Tatarakis said. "I said I was pretty sure that no talking back is in your rule book and she said, 'Oh, it is. It's on page one. I'll go to bed now."