If my daughter passed away and I don't want her husband to receive her portion when I pass, can I remove him without removing her 2 children?

I am so sorry for your loss. I am having a little trouble understanding what legal documents you may have in place at this point in time.  If you have a Will that leaves your daughter a portion of the estate there should also be a paragraph as to what happens should she predecease you.  Have an attorney review it for you.  You may want to change it and leave the money to the children in a trust fund and appoint a separate person as the trustee of the trust.  You have to rewrite the document and yes you can leave it to them and not him.  Good luck.