Is the vibe seat different to the dash one? (We have a dash). I wouldn't put a newborn in the toddler seat... I'd wait til bubs is at least 4 months and even then not if they don't have good head control. Newborns should lie flat. I'm sure your DS will get used to the seat - is he complaining, or is it just that he looks funny in there? DD likes being up in her "high seat" so maybe make a big deal about how cool that is if he's complaining about it...?