This is a somewhat difficult question to answer because the scriptures do not explicitly touch on this subject.  We might consider the intellectual limitations of a baby or child and realize that this would limit one’s ability to truly know God, praise Him, and learn more of Him throughout eternity.  A baby has limitations, such as the ability to talk, the ability to walk upright, the ability to understand any complex ideas, etc.  On the other hand, the same would be true of one who is elderly and infirmed.  Certainly, we do not like the idea of one going through eternity with the limitations and disabilities of an elderly person. 

In eternal Heaven, there will be no time, so I think we will not think of those in Heaven in relation to time experiences, such as their age.  We have this promise in 1 John 3:1-2, “Behold, what manner of love the Father hath bestowed upon us, that we should be called the sons of God: therefore the world knoweth us not, because it knew him not. Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, WE SHALL BE LIKE HIM; for we shall see him as he is.” This does not mean that we will be God, but it does mean that throughout eternity we are assured that our frail bodies shall be transformed into the likeness of his glorious body…a body without any limitations or infirmities.  Time will no longer exist, so it seems the effect of time upon each one in Glory will not exist in anyone. 

Some have speculated that we will all be around 33 years old, which is the approximate age of the Lord Jesus when he died.  According to research, the male body is at its physical peak around 30-35 years of age.  Does that mean we will all resemble that age in Heaven?  The Bible does not teach that, so I certainly cannot teach it, either. 

We read in 1 Corinthians 13:12, “For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.”  In eternity, we will have perfected understanding and we will know everyone, even as everyone will know us.  This does not mean that we will know all there is to know when eternity begins in Heaven.  We read in Ephesians 2:7, “That in the ages to come he might shew the exceeding riches of his grace in his kindness toward us through Christ Jesus.”  Throughout eternity, the Lord will continue to show us more and more of “the exceeding riches of his grace…”  We will continue to learn of Him forever!

We do know that the bodies we now possess will be changed before we enter into Heaven.  We read in 1 Corinthians 15:50-53, “Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; neither doth corruption inherit incorruption. Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. For this corruptible must put on incorruption, and this mortal must put on immortality.”  This portion is dealing with the rapture of the church and shows us how our earthly bodies are not fit for Heaven.  We have corruptible and mortal bodies that cannot exist in Heaven.  To abide in Heaven, we must have incorruptible and immortal bodies.  Every believer in the Lord Jesus Christ will go through this change at the rapture.  (Read 1 Thessalonians 4:13-17.)

Before ending this devotional, I want to assure you that all babies DO go to Heaven.  For more on this, please click on this AFTB link:  (479.6)