They could just be different little personalities. My middle baby was a more serious little soul than the other two. He was a happy Little guy but often content to sit and watch the world go by, taking it all in. The eldest would smile none stop and literally light up a room within seconds. I’m sure they’re both where they need to be and even if they’re not all babies develop at different rates. I’ve said it before but I’ll say it again, they really are adorable babies that *almost* make me broody. AlmostAre Ronnie and Rex meant to be nearl the same age? Ronnie seems way behind developmentally - and he never smiles! Whatever you say about Stacey, Rex is a lively happy little chap. Unlike some. Rather sad.