Wow, even my mom wasn't as bad as Cassandra's mom... and an interesting bit of drama added for this chapter. Although I do find it a bit hard to believe Leech Life - among the weakest of Bug attacks - would bring a Pokemon close to death, even if it was super effective.
I also think the battle between Swablu and the two bugs could have been drawn out a little. Assuming both were at full strength, I would think it would take at least two or three hits each to take them down. It would have also been a good opportunity to show Swablu in action, gracefully dodging counter-attacks while getting into position to launch its own attacks.
But other than that, I liked the chapter. The quarrel between mother and daughter helped to develop their character and relationship, and the incident with the wild Pokemon now puts a lot of responsibility on Cassandra's shoulders. It's certainly interesting how the character's paths are already starting to develop even in the early stages of their respective adventures.