Thank you both for your quick replies. I guess my reluctance is that all four girls are virtually the same age..they will all be 11 months in the fall, so there is little variance which makes me nervous. I told the mom of child #4 that I was confident that I could take her daughter in the new year...that way all the children would be at least 15-16months.

Alphaghetti- I hear you! I have to buy a quad stroller this summer and I too plan on spending much of our outdoor time in our big fenced in yard!!

Play and Learn, you have a good range of ages...I think that allows one to take on more children