Forget blood oaths or spit-soaked handshakes -- the real way to cement a brotherhood is to hold hands while chugging milk. Bonding AND your daily recommended serving of calcium!

Proud mom Kristin Cavallari, who gave birth to her second son Jaxon in May, remains hard at work perfecting her shoe collection, but that didn't stop her from catching her kids in a moment this week that was so cute, it could have conceivably stopped traffic. LET THE ADORING BEGIN.

"The boys holding hands while they drink their milk. I can't handle it ❤️❤️" K-Cav wrote with the photo above, in which Jax and Camden link up from thumb to pinky while enjoying their beverages of choice. Man, a soldering iron couldn't have cemented those hands together more tightly. Does this mean we can expect an expertly choreographed handshake by year's end?

And hey, maybe Jax can tag along to the zoo next time his big bro and mom and dad make the trip. Bear in mind, though, kid, holding hands with the wildlife will not do you any favors. We know that orangutan has his arm outstretched, but...

Take a look at Kristin's sons making an early declaration of friendship, and feel free to "aww" in the comments!