Yes, but the majority of the size is in the first year...they DO tend to grow for four years. One of my "virtual F2s" grew 2 full inches between when I saw him at 18months and 4 years of age. He didn't gain much weight though, he just got taller!
I think in general they get most their size, then they might grow an inch or two higher and then as they age they add some muscle bulk and "fill out"... but I don't think you can expect a cat to double in size or anything after a year of age. I don't think I've ever seen that...
I think in general they get most their size, then they might grow an inch or two higher and then as they age they add some muscle bulk and "fill out"... but I don't think you can expect a cat to double in size or anything after a year of age. I don't think I've ever seen that...