wondering about growth cycles and when do they slow down?

[Max&Roxy]

Max is almost 6 months old (December 11.) He is a small little guy...only around 2.2 pounds at his last vet visit for his shots when he was 16 weeks. He looks like he has grown a little taller etc. but he is still very very light...and if I had to guess, he cant be more than 2.5 to 3 pds....We have a Yorkie who weighs in at 4.5 pds and Max feels a LOT smaller in weight as she does. I know we need to have him weighed, which we will in a couple of weeks when we go for our next vet visit.

My question is.....do they slow down in their growth by this young age? Like could he grow another 10% or 20% etc? I read somehwere about averages for growth....cant remember where?

We have always thought he wouldnt get much bigger than 3.5 pds....and yes I do know that it can be a guessing game....but, he seems to be heading that way.