How to get UserId from :GetOnlineFriends()?

Hello! I've been working on an in-game friendslist recently.

For some reason, I cannot get the UserId of a user. Here is my script;

local Players = game:GetService("Players")

local player = Players.LocalPlayer
local onlineFriends = player:GetFriendsOnline(8)


for i, friend in pairs(onlineFriends) do
	print(friend.UserId)
end

Output just prints nil.

For some weird reason, friend.UserName works, but friend.UserId doesn't. How could I get the userid?