I've never done it, but it's often not recommend to get two puppies at the same time, especially with 4 females in the house. They call them bitches for a reason!

LOL. Of course, some people are successful with 4 females but I wouldn't want to try it, especially with two from the same litter. More prone to fights.
Two Puppies or One? - VeterinaryPartner.com - a VIN company!
Here's a great article.