Get-ReqServices

function Get-ReqServices
{
    param
    (
       # Service you want recursive required services from
       [string]$service
    )

    $final_list = @()
    $final_list += (get-service $service).RequiredServices

    do
    {
        $check = $final_list.count
        foreach ($item in $final_list)
        {
            if(($item.RequiredServices).count -ne 0)
            {
                $final_list += (Compare-Object $final_list $item.RequiredServices | where {$_.sideindicator -eq "=>"}) | select inputobject -ExpandProperty inputobject
            }
        }
    }
    until ($check -eq $final_list.count)

    $final_list | select status,name,Displayname,RequiredServices | Sort-Object -Property Name
}