ThenInclude like in .Net core for EntityFramework 6
Example
using System.Data.Entity.Include;
var thenInclude = context.One.Including(x => x.Twoes)
.ThenInclude(x=> x.Threes)
.ThenInclude(x=> x.Fours)
.ThenInclude(x=> x.Fives)
.ThenInclude(x => x.Sixes)
.Including(x=> x.Other)
.ToList();