From the description:
"The Cheeseman family is back from back in time. In other words, they're in the present time. Well, presently, at least. They're soon to journey back again -- only just a few years this time -- to save the life of their beloved mother. But when they get to the not-so-distant-past, they meet something utterly surprising. Something wilder than anything they've seen before -- including cowboy poets and good-natured pirates. They are about to meet... The alternate versions of themselves!"
4.7 stars off a scant 15 reviews, but they all apparently liked it. I can't find a particular age range for this one: I'm guessing grade school to early middle school, but I'm groping in the dark for that. 256 pages