Personally, 70-200 is my favorite focal length rage when it comes to fun factor, but of course that is just opinion. But I also think it is a better range for portraits than 35mm, especially portraits of small people (as no doubt your 5-mo old is).


The 35, of course, is faster, and fast lenses are fun. But you know that from using your 50 f/1.4 (which reminds me of another reason I would recommend the 70-200: it's more different from what you already have).


Opinions, you'll probably find, will vary wildly. Take mine with a teaspoon of salt.