Luke 18:15-17

People were also bringing babies [brephe, cf. Luke 1:41, 44; 2:12, 16; Acts 7:19] to Jesus to have him touch them. When the disciples saw this, they rebuked them. But Jesus called the children [paidion] to him and said, Let the little children [paidion] come to me, and do not hinder them, for the kingdom of God belongs to such as these. I tell you the truth, anyone who will not receive the kingdom of God like a little child [paidion] will never enter it.

As seen above, there are different Greek terms referring to the children in these verse:

brephe usually refers to "little ones" who are literal babies. Mark 10:16 has some of the children small enough to be picked up by Jesus.

paidion indicates that at least some of children are beyond the toddler stage.

While two different Greek terms are used in these passages,thus denoting a range of ages in the children involved, no matter their ages, these children were considered very important to Christ. Not only are adults part of his Kingdom, but so are covenant children. Even part of the Kingdom Scriptures are written to and for them (Exod. 20:12; Deut. 6:6-7; 11:19; Psa. 8:2; Prov. 1:8-9; 22:6, 15; Matt. 18:2-6, 10; Eph. 6:1-4; Col. 3:20; 2 Tim. 3:14-15, etc. - see "Chloe's covenant household - 1 Corinthians 1:11" below).

Newborns (brephe) are born helpless and completely dependent upon others. They need their mothers to feed, clean, and cloth them. To love, warm, and care for them. They need loving father's who will defend and support them.

Such are children of the Kingdom. All God's children - whether an elder, deacon, or just a saint sitting on a pew, whether an infant or toddler - are born into God's Kingdom helpless - dependent upon God for his feeding, cleansing, clothing, loving, warmth, and care. All are born into God's Kingdom dependent upon God. Royal subjects of a Kingdom are always dependent upon their King. As a little children trusts their earthly fathers in everything, so a child of the Kingdom "has" unmitigated faith (a gift) in their Father. They trust he has their best in mind. He relaxes in his parent's arms in complete and utter reliance, not caring about the rest of the world, but merely taking in the love and devotion of his parent's love.