The Dreamhouse Kings series
by Robert Liparulo
About the series: When the Kings move to a small town in northern California, they have no idea of the adventures—and terrors—waiting for them. Fifteen-year old Xander and his twelve-year-old brother David make a game of exploring the old Victorian home they move into. One night, they discover an intruder and follow him to a hidden hallway of doors. Each door transports them to far off places in long-ago times.
But not only can they go from the house to the past, people from the past can come through into their house. Someone does—and kidnaps Mom, taking her into some unknown place in the past.
The family begins a quest for Mom, which takes them to the most dangerous and fascinating places throughout time. Then the Kings learn a terrible secret: Their being in the house is no accident, and they must do much more than “simply” find their mother. -Taken from the description on the official website
From me: I just finished reading the sixth book in this series and I loved it! They get better the further in you read. I was a little bored with book one, but I'm glad I kept reading. This is the perfect series for 10-90 year olds!