S13, EP2 "Under the Small Top; Squidward's Sick Daze"
Squidward's house becomes infested with a mail-order flea circus meant for SpongeBob; Squidward fakes being sick to get out of work, but his agony only begins when SpongeBob arrives to care for him.
S13, EP1 "A Place for Pets; Lockdown for Love"
When customers bring pets into the Krusty Krab, Mr. Krabs soon realizes pets are more profitable than owners; Plankton ruins another date with Karen, so she puts the Chum Bucket on lockdown until he proves his affection.
S13 "Pat the Dog"
Patrick is sent to the pound for acting like a worm, but he won't be able to leave unless SpongeBob can train him.