EF Core Multiple Foreign Key mapping is causing an issue

I am working with EF Core 5.0 in an ASP.NET Core Web API.

I have an entity called Child

public class Child
{
    public Guid Id { get; set; }

    public Guid FirstParentId  { get; set; }
    public Guid SecondParentId { get; set; }

    // Some other properties 
}

The above child is a property in two parent tables called FirstParent and SecondParent:

public class FirstParent
{
    public Guid Id { get; set; }

    public Child Child { get; set; }
    // Some other properties 
}

public class SecondParent
{
    public Guid Id { get; set; }

    public Child Child { get; set; }

    // Some other properties 
}

While configuring the foreign key relationship, I followed FluentAPI as follows in

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<FirstParent>().HasOne(a => a.Child).WithOne().HasForeignKey<Child>(b => b.FirstParentId);
    modelBuilder.Entity<SecondParent>().HasOne(a => a.Child).WithOne().HasForeignKey<Child>(b => b.SecondParentId);
}

While creating the tables, it created as excepted. But while inserting some data into the FirstParent, I get an exception:

The INSERT statement conflicted with the FOREIGN KEY constraint "FK_Child_SecondParent_SecondParentId". The conflict occurred in database "Tester", table "dbo.SecondParent", column 'Id'.

I cannot create all the child tables for every parent as I have lot of dependencies.

Am I missing anything more to configure? Any solutions?

Thanks in advance