Prince Thibaut was considered as the rebel of the family; he didn't have (as most of his siblings) good relations with the late Count of Paris, and against his wish Thibaut married a commoner 7 years older than him, Marion Gordon-Orr. The marriage was considered unequal by the Count of Paris, who also refused to help financially his son after he married.
Thibaut and Marion had together two sons, Robert (the present Count of La Marche) and Louis-Philippe, who tragically died of sepsis aged 8 months, in 1980. The Count of Paris, who considered Thibaut's sons as non dynasts, didn't allow the burial of Louis-Philippe in the main crypt of St. Louis Chapel in Dreux, but only in a side chapel (where later was buried also Thibaut).
Thibaut and Marion worked firstly as writers, publishing some books, and later they opened an art gallery near Paris.
The death of his son was a hard bop for Thibaut; in 1981 he was involved in some scandal (I don't know what exactly, any informations would be very appreciated), he spent 14 months inprisoned waiting for the trial and then he was condemned to one year of jail.
After serving time, he moved to Central African Republic, where he worked organizing safaris for tourists.
On 23 march 1983 he was found dead; he was only 34, and wasn't suffering of any illness; officially he died of pericardial effusion, but this thesis didn't persuade his wife and his brothers, who soon maintained that Thibaut was murdered.
In 1989 an inquiry was conducted for clarifying whether the murder occurred or not; Thibaut's remains were exhumed for an autopsy, that showed that he wasn't suffering of any illness, disproving also the official thesis of the pericardial effusion; but at the same time, no elements confirming the thesis of the murder came out, so the inquire was closed.
After Thibaud's death, Marion moved to Thoiry with her son.
At the death of the Count of Paris in 1999, his successor Henri (the present Count of Paris) annulled the decision of his father about the marriages of his brothers, and confirmed the status of dynasts of his brothers Thibaut and Michel (the Count of Evreux), their wives and children.