From: Rabbi Moshe Sofer
To: Unknown recipient
When a father died leaving outstanding loans and a posthumous daughter, the Chasam Sofer rules that daughters' maintenance can be collected from those loans, since the personal obligation to maintain daughters arises at marriage through the kesubah condition, enabling collection via shib'uda d'Rabbi Nasan. Therefore the maintenance expenditures are attributed to the loans, preserving the muchzak assets from which the firstborn takes his double portion.
Source: Shu"t Chasam Sofer EH I §144