A big thank you first for allowing me to read this one, it was big on my list to read, sadly, I didn't click with it. I got around 50% and then I just stopped.

I loved the art, that is also one of the big reasons I wanted to read this one.
I like the ideas of two siblings finding a common ground and make up a fun story for their younger sibling.

Sorry, but the mention of FFS, even when explained didn't erase the meaning that everyone will have. I kept laughing. Sorry, but for me FFS is For Fuck's Sake. Not Forever Fighting Sisters.
I didn't expect Kennedy to be 8, I thought her to be 10-ish.
Parents, if you have NO room for your kids, DON'T have another one. I felt for the girls. Kennedy, almost a teen stuck with her 4 year old sibling and also with a crying baby. On that note, maybe place the baby somewhere else? Those girls also need their sleep. Not to mention the parents being surprised the kids are out of bed, geez, if you have a living alarm clock next to you anyone would be up and running.
While I like the idea of the siblings making up a story, it was just WAY over the place for me, too chaotic, and the constant distractions (Kennedy making a remark or Devon making up something) just was too much for me.
Why would you give your 4 year old a spider when your apparently 8 year old is TERRIFIED of them? If they lived in different rooms I wouldn't have minded, but now I found it an odd choice, bribery perhaps?