Nobody is more loyal and can care with as much stability/security/solidity as the SJs, esp., the ESFJ & ISTJ. One goes all out with their feeling, the other keeps it calm and cool in quiet (but, resounding) actions that speak louder than words. Sometimes, they both see the glass as half-full and a bit too invested in [sometimes, nagging] other's lackadaisical attitudes about life - esp. if the individuals involved are directly connected to each other's lives. But, that's because, they need to think on the long-term security, and thus, have such attitudes, to prepare for the worst (for us all, not just them - the dutyfillers). And, very honest, ISTJs. Only 'dishonesty' would be in terms of 'lies of omission', but, that may be a lot of the I as well. And, my ISTJ x-roomie actually (dare I say) indulged me/humoured my quirkiness that is ENTP, and we even were open to learn from each other. She liked my go-with-the-flow, optimistic attitude, and I liked how she exuded consistency and quiet determination.
My ESFJ best friend has been my lifelife for motivating me towards practicality in school/career/daily living. "Trying" to teach me to cook. I just mastered boxed Mac & Cheese (woo, Kraft). She even buys groceries for me, in practical methods/ways/packaging [or packages them herselves into 1 plate portions in ziplock bags]...so I would feel motivated to cook for myself. [I sometimes, weirdly, would rather starve than make the effort to make food/cook for myself...it's boring to me, cooking, and if it's a bore, I am not motivated, even for hunger]
But, yeah, my ESFJ friend, her efforts go above and beyond. I've never felt such care.
And, my ESTJ dad. The steady rock of the family. Esp. counter to my INFP mom. Paradoxically (even with their fiery arguments sometimes)...the perfect pair.
SJs= They are fiercy loyal [and solid in that loyalty] to ones they care about/love.