Blaine goes back to NYADA to study acting and singing and Kurt goes to his Broadway audition to be in Dear Evan Hansen while Rachel watches the baby.
After Rachel has Kurt and Blaine's baby girl, things start to change between the two of them. This is when Rachel started to get worried. Kurt is almost never home, and whenever he is, he is to tired to do anything. Same with Blaine
Later that night, Rachel wakes up to hear Kurt just coming home at 3 in the morning. “Where have you been” Rachel asks as Kurt replies “I went out” and goes to bed. Rachel plans for Jesse (Her husband) to watch the baby while she spies on Kurt the next morning
Kurt is seen going on the train back to Lima. She follows Kurt all the way there to what she is shocked to see.
Kurt’s mom tells Kurt, “I'm so happy you can come on such short notice, I'm really going to need you in a time like now.”
Rachel follows them to a cemetery where there lays Burt Hummel 1969-2020. Died of cancer and missed by all. Rachel was shocked.