Need help with LINQ Query - Order by bool, then parent -> children

[Krokonoster]

Hi,
I'm showing a list of services which have the following members (removed non-relevant ones):

        public string Name { get; set; }
        public bool Compulsory { get; set; }
        public IList<Service> ChildServices { get; set; }
        public Service ParentService { get; set; }

I want order showing the Compulsory one's first (though not so important), then showing each that have sub-services, then it's sub-services...make any sense?
Like
Service 55 (Compulsory)
Service 2
Service 2A
Service 2B
Service 3
Service 3B
..etc

At present I'm just ordering by compulsory and then name

model = _repository.GetAll().OrderByDescending(x => x.Compulsory).ThenBy(x=>x.Name);