Here is some material I posted about "least ones" in Matt 25: (See also this thread.)
Good points about who Jesus' brothers are. The Society always goes to Hebrews chap.2 to define this rather than stick to Matthew which would provide the closest context for the wording of the parable of the sheep and goats.
In that parable (Mt 25:31-46), Jesus called his disciples, "the least of these my brothers" (v.40) and "these least ones." (v.45) "Least" (Greek elachistos) is the superlative of mikros, translated "little ones" in Matthew and Mark. It is interesting to see how "little ones" are described:
Mt 10:42 "disciples"
Mt 18:6 "who put faith in me"
Mk 9:42 "that believe"
Another point of note is that the Society says the "brothers" can't be the same as the sheep since they are both referred to in the same context. Yet just a few verses earlier they say that the 'faithful slave' is the same as the "domestics," even though they are similarly used in the same context. (Mt 24:45-47) Their logic is whatever it needs to be to maintain their 'flashes of light.'
(Incidentally, the logic in the paragraph above might not work anymore since the Society recently changed their meaning of who "the faithful slave" is. Thus, in the Society's newest interpretation, "the faithful slave" is not the same as the "domestics.")
A good counter verse is Hebrews 6:10 where those Jewish Christians "have ministered to the holy ones." Using the Society's logic, that would mean that those Jewish Christians could not themselves be "holy ones" since they "ministered to them." Same with Matthew 10:42 where anyone who 'gives a cup of water to someone because he is a disciple' would not lose their reward. By the Society's logic, giving a cup of water to one of Jesus' disciples would prove that the giver was not a disciple. Pure nonsense.
One of the biggest things (to me) that disproves the Society's explanation of the sheep and goats parable is the fact that the Society has to dispense with what Jesus said the sheep would do. In the parable, the sheep give personal help to Jesus' brothers. This is definitely doable if the "brothers" are Jesus' disciples. But by identifying these 'brothers' as the 144,000, because there are so few and no one can know for sure who is, it becomes impossible to do what Jesus said the sheep would do. The Society replaces their actions with, 'help in the preaching, obey the elders, and give money to the Society.' [See w09 10/15 pp.15-16 pars 15-18]
In connection with "brothers" in Matt 25:
The best thing to use is Jesus' description of who his brothers are. It can be found right in Matthew itself - 12:46 - 50
Hope this helps
Take Care