Hello, our house was built in 1928 and we recently purchased the home. We have two sets of stairs and the photo shows that in our stairway on the 2nd level there is a crack in the ceiling which is where the staircase is leading to the 3rd level.

Any thoughts on immediate concerns or recommendations on how to fix this and make it looks seamless?

There is also a crack on the other stairway from the main floor to the 2nd level.