Travelling to Europe with a baby????

Hi all. We are considering a trip to Europe. Actually we have wanted to do it for a long time. Our kids are now old enough (11 and 8) to enjoy the holiday and not find it (or make it...) difficult to make such a long trip.

But theres a baby on the way. So two things I am wondering.....

What is the best time of year to see Europe?

Am I crazy thinking about taking a less than 1 yr old on a trip like this?

I havent done it, but when I flew to London the couple next to me had a baby in a capsule, and he was really good with the flight - no idea on the holiday, but between bf and sleeping I barely knew he was there.

No definlty doable. I would do Europe in there summer as winter is gray and rainy