Help! my daughters got silly putty on a blanket that I just got done knitting for the 7 yrs. old birthday. Any suggestions on how to get it out without ruining the blanket.

You aren't alone! Here's some other threads with suggestions for what might be done:

http://www.amitymama.com/vb/showthread.php?t=235364
http://www.amitymama.com/vb/showthread.php?t=227332
http://www.amitymama.com/vb/showthread.php?t=241236

Hope this helps!