Jonathan was the grandson. WFB's son is Christopher. Yes, WFB was free to do whatever he wanted to do. He was even free to write this in his will about his grandson:...His son (Jonathan) fathered a bastard child. WFB didn't leave the bastard any money. He left it to his son and 2 legitimate grandchildren. Jonathan is free to give all the support he wants to HIS bastard.
"I intentionally make no provision herein for said Jonathan, who for all purposes ... shall be deemed to have predeceased me."
Stated differently, "He's dead to me." How very classy to include that passage about his 7-year-old grandson in his will.
I don't see any problem with that.
Of course you don't.