Sam wakes and gets Ruby ready for school and later they talk about Ruby's fight in episode 3x02 “Triggers”. Lena stays at Sam's house after the attack during her press conference in episode 3x05 “Damage”. Sam wakes up from a nightmare and realizes she doesn't remember her trip the day before in episode 3x09 “Reign”.
Appears in 3 additional episodes.
Source: AprilBC23 — Twitter