purebornbaby-boys White With Cross White With Cross

I have a 4 month old who weighs 15 pounds, he looks like he is 6month, should I order 3-6 or 6-9month?

Is this white or an off-white? I’m hoping it looks more white.

Is the “White-2” option a bright white or is it more of an off-white/ivory?

Does it come with a bid like in the picture?