Harry Potter and the Crazy Baby Night

Severus has survived the Second Wizarding War and succeeded in protecting his new love, Eliza and their baby son, Septimus. Now Snape continues to teach as a DADA professor. When Eliza and Severus go for a romantic dinner date, Hermione, Ginny, and Luna are left to care for Septimus. What would this date night lead to and is the Trio capable of babysitting Snape's child?