Because during most of filming of season 3, Marshall had longer hair there are several flashback moments of Marshall in the time line of the first two seasons where he has long hair, but when the first 2 seasons actually took place he had shorter hair. See more
I think we're going to wait on the baby thing. I mean I love babies. Babies rule. Pudgy arms and stuff. But, uh, they make you old. Kinda like this anchor weighing you down to one spot... forever.
I'm three months pregnant.
Not awkward, guys. Not awkward if we don't let it be awkward.
[nervously smiles, then walks away