Actually, as soon as Di Yelei returned, Liu Sisi knew.
Guihua, Feng'er, and Di Ying had been keeping her company for a long time, and the anger that had been deeply buried in her heart was finally dissipating.
Zhang Peng was now rising steadily through the ranks, having been appointed as the Assistant Minister of Ministry of Storage, a fifth-rank official, in the powerful Privy Council that oversaw the Ministry of War. This was a substantial post, and naturally, he also received an official residence allocated by the imperial court, much to Guihua's delight. However, given Liu Sisi's current bad mood, she naturally stayed in the Di Residence.
Upon hearing of Di Yelei's return, she promptly feigned exhaustion with an adept eye, and even Di Ying happily looped arms with Guihua, pulling along his future mother-in-law, and they each went back to their respective courtyards to rest.