Children of Mariota Cardney and father

Here's about Sir John Steuert of Cardney

https://books.google.com/books?id=-TEOAAAAQAAJ&lpg=PT104&ot...

Page 4 of Modern Athens! Displayed in a Series of Views: Or Edinburgh in the ...
By John Britton, Thomas Hosmer Shepherd

Sketches of the Olden Times in Perthshire By Robert Scott Fittis

https://books.google.com/books?id=CGvvAAAAMAAJ&lpg=PA242&ot...

Bishop Robert Cardeny was her brother --https://books.google.com/books?id=tr9VAAAAcAAJ&pg=PR37&dq=m...

she appears to be the daughter of John de Cardney, of Cardney and Foss:

https://books.google.com/books?id=8JcbV309c5UC&pg=RA2-PA563&amp...

To answer the question of whether Mariota’s 4 sons by Robert ll are valid, Medlands only shows this in their Robert ll article

http://fmg.ac/Projects/MedLands/SCOTLAND.htm#_Toc389122947

King Robert II had one illegitimate son by Mistress (1):
15. JOHN Stewart of Dundonald (-[1445/49]). "The Black Stewart". Sheriff of Bute. m firstly JANET, daughter of JOHN Sympil of Elistoun & his wife ---. [1244]m secondly (3 Feb 1408) ELIZABETH Graham, daughter of WILLIAM Graham of Kincardine & his wife ---.

Have you looked at what the Scots Peerage claims ?

https://sites.google.com/site/thescotspeerage/scotland-house-of-ste...

Transcription of TSP, might be easier to read. Lists the children by mistress without naming their mother (s)

No mention of Mariota de Cardney

http://www.thepeerage.com/p10210.htm#i102097

Rotuli Scaccarii Regum Scotorum: The Exchequer Rolls of Scotland, Volume 4 Scotland. Court of Exchequer General Register House, 1880 - Scotland page 169

https://books.google.com/books?id=Ke4_AQAAMAAJ&lpg=PR169&ot...

Copy & paste:

Sir John Stewart of Cardney

On 15th January 1382-3, John Stewart, the King's son by Mariot Cardney, had a charter of Kinclevin, Ervyntoly (Arntully), Tulibeltyn, and Dulmernok, with remainders to his full brothers Alexander and James.

In the Chamberlain’s account of 1394 occurs a payment of £10 to Master Robert of Cardney, to the expenses of the King’s brother John Stewart, studying at Paris.‘5 There are remainders to this John Stewart in the above mentioned charters of 1378 and 1382-3 granted to his full brothers James and Alexander, and his halfbrother John. Robert III. granted a charter of the two Cardneys in Perthshire to his brother John Stewart,‘3 which is said by Duncan Stewart to have been dated 12th February 1399, and to have contained a reversion to a younger brother named Walter.7

Sir John Stewart of Cardney was made a knight at the coronation of James 1.8

Arntully and Cardney continued to be possessed by his descendants.

It looks like Walter was the youngest and Sir John the oldest?

"The absence of all mention of Walter in the charters of January 1382/3 seems to suggest that he was not born till after their date."

You are correct on Walter being the youngest. I added bio in Mariota's profile and have to copy that to the children.

https://wc.rootsweb.ancestry.com/cgi-bin/igm.cgi?op=GET&db=floc... citing Stirnet has Mariota born 1318 in Dundonald Castle, Irvine, Ayrshire, Scotland

Is that right? I would think her born in Cardney lands?

(Answering myself) that date of birth / location are way wrong. She could have been born as late as 1362 (Walter b 1383 minus 21) and of the Barony of Cardeny in Perthshire. Her son John inherited from her.