When Rainbows Cry (Book 2 in the Rainbow Quest series)
Living in a Domed London of the future, 14 year old Petra Sucher is frustrated with the demands her parents place on her as unpaid babysitter for her 4 year old twin brothers. So she does what every teenager would in this situation – she conducts illicit activities. They lead her on a cross-dimensional adventure with an octogenarian and genetically engineered chimpanzee in tow. Together the three of them will either destroy their existence, or be the saving of it.