Krum had at least one brother. Dukum who ruled for a very short time after Krum's death is thought to be his brother. He died in 813 or 814.
Dicevg who also ruled for a short time after Dukum is thought to be either a second brother of Krum or the eldest son of Krum and therefore an older brother of Omurtag. Dicevg is claimed to have become blind, perhaps in old age, and Omurtag became Khan in his place (Dicevg may have been murdered by his own people). Identifying him with a brother of Krum is seen more likely, possibly due to him "becoming blind in old age"
Krum had a sister whose name wasn't mentioned. Krum married her to the Byzantine defector Konstantine Patzikos (Son of Pacik or Patzik). The couple had at least one child, a son who was old enough to join his uncle in war in 813.
Edit: I couldn't find the source for Konstantin Patzikos among my notes but found a new one which mentions other defectors.
Malamir and Enravota had an older brother, Enravota (Also called Voin and Boyan) who was deprived of the throne possibly due to him converting to Christianity. He was killed by his brother in 833 after refusing to renounce Christianity.
en.wikipedia.org
Boris Mihail had a sister, Anna, who converted to christianity during her captivity in Constantinople. His daughter Anna was named after this aunt.
en.wikipedia.org
Boris had two daughters with Maria, Eupraxia and Anna(also another daughter by a mistress). Currently only Anna exists and she is older than she should be.
Tudor Duxov (Theodore Doxov), Son of Dox, the brother of Boris Mihail.
Anna, the younger sister of Tsar Simeon is married to Tarkan Simeon.
Marmais, who exists in game but is way older than he should be, is thought to be either the descendant of the Severians in the Balkans (Slavun, a Severian prince in Balkans was raiding Thrace and was captured by Byzantines in 767) or a member of the Krum family.
Salan, who exists in game, is also a relative of the Bulgarian Khan according to Gesta Hungarorum.The source itself isn't that reliable but many elements from it already used in game.
Vladimir-Rasate had two wives. I've already mentioned Kupetra who is the second wife in my previous post and added a source but couldn't find anything on the first wife.
Olga of Kiev who is claimed to have been from Pskov which was called Pleskov may have been a member of the Krum family as well. There are two theories regarding her ancestry, one suggesting she was a descendant (daughter) of Helgi the Seer and the second is that she is a Bulgarian princess and she was not from Pskov, which was previously called Pleskov(Плѣсковъ), but rather from Pliska(Пльсковъ, romanized spelling: Plĭskovŭ ) the Bulgarian capital. The Bulgarian origin theory suggests she was the daughter of either Vladimir Rasate or Simeon. Since Simeon's children are known, the former is more likely.
There are more missing members of the ruling family of Bulgaria but I'll add them in a later post. One more thing while ending this one. Kometopuli are also thought to be members of the Krum family who are descended from either Vladimir Rasate or Gavril (brothrer of Vladimir and Simeon, not their uncle the brother of Dox and Boris Mihail). Anna Komnene, whose maternal grandmother Maria was a Kometopuli) herself says in Alexiad that she was a descendant of "Shishman Mokros" with Shisman being the father of Samuel. Mokros is found to be a copying error of Kromos and because Samuel's father is known to be Nicholas, Shishman is thought to be his monastic name.
This bit comes from things I've read on several sources I'll start with adding two.
"Chapter 8 An Antidote for Balkan Nationalisms: Samuel and the Struggle for National Consciousness in Macedonia" published on 20 Feb 2019 by Brill.
brill.com
This book is a revisionist account of Samuel’s State and the legendary struggle between Samuel Cometopoulos and Basil II (10th-11th century). It goes beyond the standard approach to the study of state formation, presenting an entirely new analytical framework which interrogates how...
books.google.com.tr
The second one I've just found, this is not one of the sources I've previously read for Kometopuli-Krum connection but is also related.
Edit 2: Another source for Kometopuli-Krum connection
https://bg.wikipedia.org/wiki/Никола_(комит)
Using google translate for the relevant bit: "The origin of Nicholas and his sons is also disputed. Among the historians of the nineteenth century there is a widespread opinion that the family of comite Nikola originated from "Shishman Mokri" and in support of this thesis they point to an information of the Byzantine princess and writer
Anna Komnena (a distant descendant of the Bulgarian royal family in the 992th century):
"... the Bulgarian basileus Mokros and his descendants, especially Samuil, the last of the Bulgarian dynasty ...". But after the
Samuil inscription from the village of German, Prespa (from 993/<>) and the Vienna manuscript of the chronicle of John Scylitzes with the additions of Bishop
Michael Devolski (from the beginning of the <>th century) were discovered, it became clear that the name
Mokros was the mistake of a Byzantine copyist of the <>th century, who distorted the original "Kromos" i.e.
Krum, which should mean that Nicholas and his sons were direct descendants of the Bulgarian ruler."
I'll try to add sources to ones that lack it later on.
www.doaks.org
