Oh my gosh. I stuck through the entire Brown Family series and the Delicious trio because I'm a completionist that way. After that mass consumption the trend was clear and they can all be given the same review.
There are two types of scenes in these books. Characters are either having sex or complementing each other. It is a mutual appreciation society. They are boosting their friends' damaged self esteem telling them that they are amazing and deserving of happiness, celebrating friends' amazingness, or being supportive as a friend works through trauma from their past.
I dare you to find another theme.