Your parent has been flagged to death, but they are simply wrong. All ceasefire agreements so far have called for the release of all hostages. By far the majority of released hostages got their freedom via a temporary ceasefire. A call for ceasefire is by extension a call for the release of hostages.

Hamas has always maintained that they are willing to release the hostages in exchange for a permanent ceasefire.

On the international stage it is actually the actors who are against ceasefire (primarily the USA) who have vetoed all resolutions which calls for the release of hostages.

It is actually the reverse, those against a ceasefire are those who are preventing the hostages from being freed.