Need advice on a new lens - Nikon

[Starbuck]

Hi guys!

I mainly work with Nikon D60 and I have just got my hands on a D3100 to which I will be switching over as soon as I get a hang of it. I do a lot of portrait photography, mostly families and kids, and right now shoot with Nikon D60 and 50mm 1.8. I love this lens, the images are sharp and just in general beautiful. the one problem I do find is shooting kids who are moving a lot, while 50mm is very fast, I find that with manual focus I sometimes miss the good shots and miss that zoom out option.

sooooo I need your advice, I am in a good mood and want to buy myself a Christmas gift in a form of a new lens, preferably with a zoom, auto focus, but still sharp as 50mm, or even a prime lense with Autofocus...it needs to be good portrait lens, what do you suggest considering I will be working with the D3100 and in a year or so upgrading to D7000??
my budget is about $500, but would like to spend less if possible so I can save some money for the D7000.

What do you shoot with when it comes to very fast toddlers?? I swear sometimes they move at the speed of light...

Thanks a bunch for your help!

[OsmosisStudios]

Sell the current 50, get the new 50mm f/1.8 G AF-S. Save the rest.

[zona5101]

Originally Posted by OsmosisStudios

Sell the current 50, get the new 50mm f/1.8 G AF-S. Save the rest.

+1 (and a few more characters to make 10)

[Starbuck]

That's what I was thinking as well...but then I have to sell and hate selling...lol

What are your thoughts on 35mm 1.8 Af-S??

[zona5101]

Originally Posted by Starbuck

That's what I was thinking as well...but then I have to sell and hate selling...lol

What are your thoughts on 35mm 1.8 Af-S??

that would be a good choice. It's not quite the portrait length so for those frame filling face shots you have to be right on top of the subject...but the upside is the wider field of view for group shots.