Travis and Libby are only 16 months apart. This small age gap means that they're close enough developmentally to either get along great or drive each other crazy.
Most days are a mixed bag of kindness and fighting. Because kindness is usually much quieter than fighting, those less pleasant exchanges tend to stand out.
Then, there are the tender moments that remind the two of them (and me) that their intense feelings all stem from love. Love with a dash of annoyance.