Illegit son - knighted 1399 "Both he [Sir John Snr] and his son, Sir John, were present at the coronation of Katherine de Valois early in 1421, the younger man having already been made chamberlain of the household of the new queen, to one of whose ladies-in-waiting he was married." https://www.historyofparliamentonline.org/volume/1386-1421/member/p...

JOHN PELHAM, KNIGHT

• 222 Writ. ‡ 14 February 1429. [Stokes].
• SUSSEX. Inquisition. Lewes 9 March 1429. [Otteworth].
• Jurors: Richard Lyvet ; Richard Rakle ; Roger Lecche ; John Bray ; Robert atte Forde ; William Stopham ; Thomas Copyn ; William Shoeswelle ; Laurence Curteys ; Robert atte Reede ; Henry Westbourne ; and Thomas Warde .

He held no lands or tenements of the king in chief or any other in demesne as of fee. For service rendered, Henry IV granted him the following parcels of the castle and shire of the honour and lordship of Richmond by letters patent dated 21 November 1412 [CPR 1408–1413, p. 457]. The letters were shown to the jurors, and the grant was made to him and his heirs in perpetuity, to hold of the king, his heirs, and successors in chief by knight service after the death of Ralph, earl of Westmorland and marshal of England, who held the castle, shire, and lordship for life also by grant of ‪ Henry IV by letters patent.

• Crowhurst, the manor, annual value £8 14s. 10½d.;
• Burwash, the manor, annual value £14 12s.;
• Bivelham, the manor, annual value £7 2s. 9¾d.; with
• Hastings, the rape, annual value with perquisites of court £21 6½d. Ralph died and John was seised of the manors in demesne as of fee until he enfeoffed John Pelham, knight, junior , delivering seisin to him and his heirs in fee simple in perpetuity. The farmers and tenants attorned to him. After the enfeoffment, John Pelham had no interest in the manors or rape except at the will of John Pelham, junior , and by his licence. He died on 12 February last. John Colbrond and Joan wife of Thomas atte Hale are his kin and next heirs. John is the son of Agnes sister of John Pelham , and Joan is the daughter of Joan, his other sister. John is aged 21 and more, and Joan is aged 30 and more. C 139/39/36 mm.1–2

http://www.inquisitionspostmortem.ac.uk/view/inquisition/23-222/