Fascinating, but how is this relevant to this thread?
sorry, busy reading the bio at the moment (thought it would be useful to look at the viper pit atmosphere that Carlo Martello would be born into/grow up in):
basically, Andrew was sidelined as "little more than a barbarian" during his lifetime. He was at court in a circle of Hungarians who were pointedly excluded/treated as outsiders by the "chic" Neapolitans. He was maligned as "short", "stunted", even "retarded", a "coward" (he was supposed to lead the final invasion of Sicily of Roberto's reign, but dithered and delayed). In letters by Petrarch and others, at seventeen, Andrew is referred to as a "boy", while Giovanna is always the "queen" or "Lady Giovanna". Nobody in Naples had a high opinion of Andrew (or the Hungarian match) - imagine someone calling Edward III a "boy" at 17, or Lajos the Great.
Andrew's mom made his situation worse. He didn't "mind" the mistreatment - or at least, was used to it - until Elizabeth of Poland got involved and started badgering the papacy that he was to be made of equal rank to Giovanna/break Robert's will. Worse was when Giovanna was ill for two months - and government in Naples
ceased to function - in the summer of 1343/1344, Andrew
tried to step in and provide some form of "authority" (it was when Aymeric de Chalus was papal legate of Naples, and Chalus wouldn't move without the pope's sayso, which meant that the government was paralyzed). After that Giovanna began to see him as a rival and petition the pope to
block Andrew being considered as an equal. The papal bull declaring this arrived two days after Andrew was murdered. And had it not been for the interruption of his nurse/governess, Isabella, the murderers would've likely got away with it. Their plan was to put out as though someone in Andrew's circle had informed him of urgent news from Hungary or that his life was in danger, and he'd left Naples that way. But then got ambushed on the road and ended up murdered. Unfortunately, Isabella heard Andrew's screams (he was in his nightclothes and without even a paperknife to defend himself) as they murdered him and she got one of the guards to break the door to the gallery where he was murdered down in time to see them throwing his body over the balcony.
That said, there are three "factions" at the Neapolitan court at the time: the Hungarian (nominally headed by Andrew, but really by Elizabeth of Poland, Cardinal Colonna and Petrarch), the Taranto faction (headed by Catherine de Valois, Empress of Constantinople, Princess of Taranto, sister of Philippe VI of France) and the Durazzo faction (headed by Giovanna's sister, Maria and her husband). Around the time of Carlo Martello's birth, Petrarch was also slandering Giovanna as "light" and a "flirt", the usual accusations of adulterous behaviour (that would hound her all her life). Giovanna's "accomplices" were Robert
and Louis of Taranto, Bertrand d'Artois (another cousin of Giovanna's, and Andrew's murderer), Roberto di Cabanni (mixed-race son of Giovanna's wetnurse, Philippa Catanese, and future Grand Seneschal of the Kingdom of Naples). So should Carlo Martello survive, there are more than enough persons who are going to assert illegitimacy. Taranto, Artois, Cabanni (and his daughter, Sancia, who was in waiting to Agnes de Perigord) were all involved in the death of Andrew. And all were subsequently "rewarded" with lands/moneys out of Dowager Queen Sancia's estate (originally earmarked for Santa Chiara and Santa Croce Churches and the Franciscan order).
So Lajos removing his nephew from the - even Petrarch calls it this - toxic atmosphere of Naples is probably a good idea. There are too many people who disliked the Hungarian faction at court. However, even if Lajos only removes him as far as Colonna-controlled Rome it would be an improvement. No need to take him all the way to Hungary.
That said, Carlo Martello is likely to be surrounded by the same Hungarians as his dad was in Naples/Rome, so his upbringing will be strongly influenced by that. Strongly influenced by the stories of his dad's murder (I wouldn't count it impossible that Isabella ends up as his nurse/governess as well. Philippa Catanese was nurse to Giovanna's dad, then to Giovanna and her sister, and Philippa's granddaughter, Sancia, wound up as nurse to one of the Durazzo children). Carlo Martello is also likely to be sidelined as much as his dad was, and hopefully Lajos will have learned from the murder of his brother (which was caused by Hungarian involvement) to "stay out of it" (aside from asserting his nephew's right to succeed his mom), not sure if that's ASB or not.