yes indeed and after, dont let that other pup around them until they are at least 6 weeks old. Moms are grumpy when their pregnant and specially after they whelp, dont take the risk of your little one getting hurt!
if you need some helpo go to Debbie Jensens site for more information about whelping
http://www.debbiejensen.com/
there are lots of pictures of a whelping there too!