While I can't be sure without a whole lot of past-blog research, I want to say that Hannah might be my youngest to sit in a Bumbo. Three months old? Not too shabby! For the few months that a baby uses these chairs, I love them! I'm huge on not buying one of these however, as they use them for such a short period of time. Just borrow one from a friend! I have since heard that they require a seatbelt for safety reasons, but I am really a-ok with the traditional bumbo.
I looked back at some past posts to find where the bumbo has previously made an appearance: