Handling ForeignCollection when manually initializing parent entity

Question

I designed a model with two entities : ParentEntity and ChildEntity. I use OrmLite to store them in a database.

I actually get my data from a remote webservice. This is the process I have :

1. Request the webservice (using retrofit)
2. Get JSON string in response
3. JSON string is parsed to JSON model by Gson (thank you again retrofit :))
4. I convert JSON model to an OrmLite model (no library, I make it myself)
5. The OrmLite model is given back to the callback waiting for the response of the request
6. The callback is in charge of calling the DAO to actually store the data

This process works perfectly for simple entities. But a problem appears when I try to manage more complex entities, with a ForeignCollection for example. Actually, I can't achieve the step 4 because I can't create a new ForeignCollection to put my child entities inside it.

I found some answers saying that I should store every child myself, but it will break the step 6 of my workflow.

So the question is :

How can I initialize the ForeignCollection before getting the object from the database ?

I could find a way to change the workflow. But it's only a kind of "work-around" and will create container objects just to achieve this...

The OrmLite schema (simplified)

(The class Entity just have a property id and its getter/setter.)

ParentEntity

@DatabaseTable(daoClass = ParentEntityDao.class)
public class ParentEntity extends Entity
{
    @ForeignCollectionField(eager = true)
    private ForeignCollection<TimesheetEntry> entries;

    public Collection<TimesheetEntry> getEntries()
    {
        if(entries != null)
        {
            return Collections.unmodifiableCollection(entries);
        }
        else
        {
            return Collections.unmodifiableCollection(new ArrayList<TimesheetEntry>());
        }
    }

    public void addEntry(ChildEntry childEntry)
    {
        childEntry.setParent(this);
        entries.add(childEntry);
    }

    public void removeEntry(ChildEntry childEntry)
    {
        entries.remove(childEntry);
    }
}

ChildEntity

@DatabaseTable(daoClass = ChildEntityDao.class)
public class ChildEntry extends Entity
{
    @DatabaseField(foreign = true, canBeNull = false)
    private ParentEntity parentEntity;

    public void setParentEntity(ParentEntity parentEntity)
    {
        this.parentEntity = parentEntity;
    }

    public ParentEntity getParentEntity()
    {
        return parentEntity;
    }
}

JSON schema (simplified)

Parent entity

public class JsonParentEntity
{
    private List<JsonChildEntity> entries;

    // Getter/setter
}

Child entity

public class JsonChildEntity
{
    private String name;

    // Getter/setter
}