"We found him tucked together with his two siblings in the back yard of the Santa Cruz SPCA," mom of three Jessica Shyba writes on her blog, Momma's Gone City, of the puppy her family brought home last week.

beau 1

"Big Bird -- as he was named at the shelter -- was the shyest of them all to meet us, though he bounded instantly into [my son] Beau's lap as soon as he entered their pen. The look on his little furry face was enough to seal the deal for me, we had met our newest family member."

theobeau13

This lovable dog is not merely a family member, though: the puppy, renamed Theo, has also become the co-star of an irresistible photo series on Shyba's Instagram account, and appears to be enjoying his new home very much... particularly at naptime.

beau 3

Every day now, when Shyba puts 23-month-old Beau down for his nap, Theo follows.

theobeau6

Once Beau is asleep, she brings the puppy into his room. "He plops right on top of Beau and they sleep for a minimum of 2 hours together," she told us via e-mail.

theobeau6

Their daily naps have turned into "what I can only describe as the most organic and beautiful friendship I have ever witnessed," Shyba writes.

theobeau8

Naturally, they've inspired a hashtag: #TheoandBeau.

beau 8

"I think that Theo, having been abandoned by [his] mother early, feels like Beau is like a litter mate to him. He's only 8 weeks old now, so he's still very young," Shyba said.

theobeau10

"The most interesting part about their relationship is that while they immediately found comfort in each other, they also fight like siblings -- the roughest out of our three kids."

theobeau11

On her blog, she adds that she hopes to use the project to give back. "Time will tell where this project leads, but I have high hopes of doing a little book and donating proceeds to the Santa Cruz SPCA."

theobeau

beau 12