Two of my nephews did not follow the "normal"
pattern for talking either. One of them did not talk until he was nearly four and the other "babbled".
Surrounded as they each were, by numerous siblings and similarly aged cousins who were actually very articulate for their ages and "expected" developmental stages, their lack of progress in the communication department was very noticeable.....
I remember having long conversations about them with various members of the family. We were all very concerned and we were so worried.
We wondered how they were going to go, why they were so different, whether we were doing something different or needed to do something different and what was it going to be like for them if they were still so far behind by the time they went to school?
Well, when the one who had delayed speech did start talking at four, he turned out to be a very thoughtful chap and his speech was immediately age appropriate and we haven't looked back since. I still remember my first conversation with him, because it really was a two way affair about cricket, believe it or not! He is now 24 years old.
The other is now 13 years old and very, very articulate and well spoken.His teachers have suggested he go in for drama, because he enjoys presenting to the class so much. He did see a speech therapist for a year or so around the age of five.
I have 18 nieces and nephews and remember just how concerned we were and how scarey it was when some of them missed designated developmental stages. They have all eventually hit the marks, with no signs now of where the delays were. They were all really different from each other and looking back I can see how everything did "fit" for each them in terms of who they are and how they are. Kids are really,really different from each other.
On the size track. In one family there is a very large discrepency in size between boys,6'2', 6'4' and the other is 5'7'. In this case, the smallest is also gluten intolerant, which can make them very small with the lack of nutrition that accompanaies it. He did not discover his intolerance until he was in his twenties. There are many sites on gluten intolerance if you want to check the possibility out. Having said that, while GI can and often does affect size, making for small children, it doesn't always have that affect, even if you do have it and my nephew does have alot of Irish acencestry with restrictions in the height department. Maybe the others just came out with the dutch genetics when it came to height.
I would also like to echo the other posters.
Keep yourself informed and if you are worried or just feel the need to cover that base, see a specialist.
Peace of mind is a big thing.
Nagging doubts are a curse!
I wish you, your wife and your sons all the best!