Nuts! Was on my phone and didn't see it was multi-choice till after I voted. :?
Mimzy and Pip are roughly the same age. Pretty sure they were spring births but Mimzy's Gotcha Day is 16th July 2007 and Pip's is 17th December of that same year.
Fiver is roughly a year younger, although I don't think he was considered even a year old by my vet when we took him for his first checkup but his Gotcha Day is August 20th, 2008.