I think rose and scorpius would have three kids 2 boys and 1 girl their names would be Hadar, Vega and Castor. Hadar would be in slytherin and a prankster. Vega would be in Ravenclaw and really smart. Castor would be in Gryffindor and be kind.

Well, I found this pic of their family tree:
But you can believe what you want.
It says: (Left to Right)
Lillian Rose-Ronald Draco-Lexie Jamie-Sirius Hugo

:)