A foster baby for Christmas

We just got a call! Four days before Christmas and there is a little tiny baby needing a home. Before I could even allow my heart and mind to think about it, I said no. It was the same woman that placed baby C with us 9 months ago. She said she thought we were full, but was "hoping".
I immediately called DH to tell him, and to my surprise he was asking questions like, "Was it a boy or a girl?" and "How old?" I cannot believe he would even consider it, with how overwhelmed we are! I tell people all the time that this is our limit. I cannot imagine caring for 3 babies, plus the other two. This morning was a great example, there was one diaper change after another, one older child sick, and crying coming from every direction. It took both of us to get things under control. It was complete chaos for awhile, the kind where you need to stop and pray, because you realize you really need God's help in that moment.
But, of course, I still wonder, where will this baby end up? Who is this little one? Should I have considered it, prayed about it, instead of saying no right away? A baby for Christmas...I pray this precious one finds a wonderful family just in time.