Heth De Ros, Earl of Ross? - Sources

Aed/Ed/Heth/Beth/Head (assumed to be all the same person) witnessed some charters as a "comes" (count, earl, mormaer) in the reigns of Alexander I and David I (c. 1114-c. 1130). While none of the charters specify his realm, we know it wasn't Fife - that was held by Causantin (Constantine) of the Macduffs from c. 1095 to c. 1128.

Considering that "Malcolm MacHeth" (who may have been Aed's son or grandson) laid claim to Moray and was eventually bought off with a portion of it designated as the earldom of Ross, Aed probably came from there.

These two profiles are the same person:
Malcolm MacAlexandair
Malcolm MacAlexandair

He's Alexander's son, but *not* by his wife Sibylla. If Malcolm MacAlasdair and Malcolm macHeth are the same person (which is a popular but unproven theory), then his mother would probably have been a daughter of Aedh of Moray.

Medlands http://fmg.ac/Projects/MedLands/SCOTTISH%20NOBILITY%20LATER.htm#_To... buys it:
MALCOLM, illegitimate son of ALEXANDER I King of Scotland & his mistress --- ([1105/15]-). Orderic Vitalis names "Melcofus" bastard son of King Alexander[1]. Robert of Torigny records that "Aragois comes Morefie cum Melcolmo notho filio Alexandri fratri regis David" invaded Scotland in 1130[2].
same person as …? MALCOLM MacHeth (-23 Oct 1168[3]). John of Fordun’s Scotichronicon (Continuator) records that "Malcolmus filius Macheth" lied to claim he was "filium Angusii comitis Moraviæ" who was killed "tempore…regis David…apud Strucathroth a Scotis" and, after his alleged father’s death, rebelled against King David who imprisoned him "in turre castri de Marchemond, quond nunc Roxburgh nuncupator"[4]. Duncan suggests that these two persons were different, Malcolm MacHeth being the son of "Aed" or "Heth" who witnessed two charters in the early years of the reign of King David I[5]. It appears that Heth was the same person as Beth Mormaer [of Fife]. The Chronicle of John of Fordun (Continuator - Annals) records that "Malcolm Macheth" made peace with the king the year after his son was captured[6]. John of Fordun’s Scotichronicon (Continuator) records that Malcolm MacHeth made peace with King Malcolm the year after his son was captured[7]. He was created Earl of Ross in 1162 or before[8].
m ([1130]) [--- of Argyll, daughter of ---]. Her parentage and marriage are confirmed by John of Fordun’s Scotichronicon (Continuator) records that "Summerledus regulus Ergadiæ et sui nepotes, filii…Malcolmi Macheth" rebelled against King Malcolm IV in the first year of his reign[9]. This assumes that the term "nepos" should be interpreted as "nephews" in that source. Her marriage date is estimated assuming that it is correct that her husband was imprisoned from 1134, before which his two children must have been born. There would be no such restriction on the date if Malcolm son of King Alexander I and Malcolm MacHeth were two different persons as suggested by Duncan[10].
Earl Malcolm & his wife had [three or more] children:
1. DONALD (before 1134-after 1156). The Chronicle of Melrose records that "Dovenald the son of Malcol was captured at Witern, and imprisoned in the tower at Rokesburc along with his father"[11]. John of Fordun’s Scotichronicon (Continuator) records that "Summerledus regulus Ergadiæ et sui nepotes, filii…Malcolmi Macheth" rebelled against King Malcolm IV in the first year of his reign and that "nepos eius unus filiorum Malcolmi Macheth, Dovenaldus" was captured "apud Quhythern" and imprisoned "in eadem turre de Marchemond cum patre suo"[12]. There is no mention of his having succeeded his father as Earl of Ross, suggesting that Donald predeceased him.
2. son(s) . The Chronicle of John of Fordun (Continuator - Annals) records the rebellion of "Sumerled kinglet of Argyll and his nephews the sons of Malcolm Macheth" in the first year of the reign of King Malcolm IV[13]. The number of these other sons is not known.
3. HVORFLAED [Hvafleda or Gormflaeth/Gormlath] (before 1134-). Orkneyinga Saga records that “Hvarflod, the daughter of Earl Malcolm of Moray” was the second wife of Earl Harald[14]. The Chronicle of John of Fordun (Continuator - Annals) records that "Harald the earl" was "goaded on by his wife, the daughter of Mached" to rebel against King William in 1196[15]. m as his second wife, HARALD Maddadsson Jarl of Orkney, son of MADDAD [of Scotland] Earl of Atholl & his second wife Margaret of Orkney (1134-1206).

Wikipedia doesn't buy it:
https://en.wikipedia.org/wiki/M%C3%A1el_Coluim_mac_Alaxandair
Máel Coluim's eventual fate is unknown. He was, and to a large extent still is, confused with Máel Coluim mac Áeda, son of Áed, later Mormaer of Ross.
https://en.wikipedia.org/wiki/MacHeths
The main controversy concerning the MacHeths is their origin. The key question relates to the paternity of Máel Coluim MacHeth, the first of the kindred known. The present orthodoxy makes Máel Coluim the son of one Beth (or Áed or Eth), Mormaer of Ross, who witnessed two charters in the early reign of David I.[1] Earlier theories involved conflating two persons generally now seen as distinct: Máel Coluim MacHeth and Máel Coluim mac Alaxandair, an illegitimate son of Alexander I.[2]

In any case Malcolm (or the Malcolms) caused trouble for King David I early in his reign, and at least one (possibly both) of them was imprisoned from 1134 to c. 1157.

The son(s) of one or both of them sided with Somerled of Argyll against Malcolm IV, but "Malcolm MacHeth" was reconciled to his namesake c. 1157 and granted the earldom of Ross, which title he held until he died in 1168.