My 3yr. old chihuahua just had her very 1st littler and my 2 other female dogs are curious. What do I do?

I have 3 female dogs and one just had her very first litter three days. Obviously I'm not going to just let my other two female dogs get close to the new puppies but need to know how long I'm supposed to keep them away before it's okay to introduce them and allow them to be around the new mama again. One of them now walks around with a stuff toy and treats it like a real baby and they both whimper all the time when they hear the new puppies. Mama is doing awesome and is very tentative and usually has a calm and loving nature but due to hormones and motherhood her mood has shifted and she is very protective but that's understandable I just feel bad for her once very good playmates!