From: Rabbi Moshe Sofer
To: Rabbi Leib
The Chasam Sofer rules that the adult son David's inheritance should be released to him directly, as Torah-mandated heirs cannot have a guardian imposed upon them as adults, and the only basis for maintaining guardianship is fulfilling the deceased's wishes per the Sma. Regarding the absent son Nachum's share, while SA CM 285 restricts relatives from taking possession of an absent person's property, the Chasam Sofer concludes that the guardian should invest using a heter iska and transfer the funds to the father, since CM 285 itself recognizes a father's right to manage his child's property.
Source: Shu"t Chasam Sofer CM §158