I'm not ready!!

As we were driving home today, Isabella told me she wanted 4 kids one day--2 boys and 2 girls. She then proceeded to ask how babies were made. Ahhh!! I was prepared to have this conversation when she got older, but not quite yet at the age of 4. I sat there, silent, for a few moments, and then said "mommies and daddies make babies." Of course she asked how. To which I answered "they love each other so much that they make a baby." Isabella looked at me and said "they have babies by hugging??" Mommy replied "Something like that!" Thankfully, she moved on to another subject. How do you explain the birds and the bees to a 4 year old? For now, my response will have to do, and we can revisit when she's older :)