New family dynamics and unwelcome changes confront rising seventh grader Ava as she navigates her first time meeting her father's new girlfriend.Ava, an Iowa native and lover of hot fudge sundaes, secretly hopes her dad will have a minor accident, something just bad enough that they'll have to cancel their trip to meet Jenn, the woman he's dating. Ava's mom died shortly after giving birth to her, and it's been just her and her dad ever since. According to her new therapist, who diagnosed her with an anxiety disorder, Ava struggles with change, needing time to adjust to transitions. Even before leaving rural Iowa for their vacation, she finds herself awash in new, Colorado-related fears, such as catching the plague from ground squirrels or suffering a road rage accident in urban Denver. Meeting Z, Jenn's 12-year-old daughter who seems to delight in triggering Ava's fears, isn't exactly a highlight-but the most terrifying news is that her father has rented a mountain cabin. This character-driven novel proceeds at a measured pace, exploring themes around family dynamics, self-acceptance, and making your voice heard. The author doesn't tie everything up in a neat bow in the end but instead shows the complications of life, messy but loving families and all. Most characters read as White; Rodrigo, Z's father, is cued as Latinx.Will feel relatable to many tweens, especially thoughtful readers in blended families and those struggling with anxiety. (Fiction. 9-12)