So, uh.
The year is 1229 and the first Emperor of the Latins has reigned for twenty-five years. In that time, you note, he has birthed eleven children, three with his first wife Marie, then with his decades-younger Princess Beatrix, first daughter of the Holy Roman Emperor. Although Baudoin is now fifty-eight, the wife is now pregnant with another. The law is Gavelkind, but only four of those eleven are still alive; half of them didn't make it past their sixth birthday.
More interestingly, we note, that the Holy Roman Emperor recently passed away, and the emperorship passed too to another family. But Baudoin's wife somehow retains Dukedom of two duchies - Teck and Schwaben - in the heart of Germany, which she rules directly. Moreover, she has just become the ruling Queen of Sicily following the death of young King Eugenio, a relative in the von Hohenstafen family. Finally, around the same time, Beatrix's mother, the widowed Eirene, has inherited - as an Angelos - the Thema of Epirus, which is part of the Byzantine Empire.
Of course, if Baudoin should have only one living son when he, Beatrix and Eirene snuffs it, then that son will inherit the Latin Empire (currently the Thrace region & Samos), the Kingdom of Sicily, the two German Duchies, and the Thema of Epirus away from the Byzantines. I think. Maybe some of those become invalid if the son should become Emperor first, or something.
Basically, completely inadvertently, a single marriage has spawned a situation where the kid could inherit from four different kingdoms.