You are looking for an heir.

The plot is about a Scottish Earl who is looking for an heir.

Meanwhile, Andrew is looking for an heir for his industrial empire, in particular a foundling like himself.

When they grew old, they wandered away looking for an heir to some peculiar power which Nyx had never explored.

"Ronnie claims to be looking for an heir to his estate, but it's not like he did anything to earn the estate.