Can someone help me with this treeing script?

This kind of tree isn't the one with leaves and a stem, but a hierarchy of parent and child instances. I used a for loop to find what was in my designated point...

for _, v in pairs(game.Workspace:GetChildren()) do
    if v:IsA("Part") then
        print("Part found")
    end
end

At that point I realized "Hey, I could make something that searches models!". My goal of that was to do the above script, but if it found a model start the process again but have that model as the search point.

local a = game.Workspace
local b

function Tree(location)
    loc = location:GetChildren()
    for _, v in pairs(loc) do
    if v:IsA("Part") then
        print("Part found")
    elseif v:IsA("Model")
        b = v
        Tree(b)
    end
end

for _, v in pairs(a:GetChildren()) do
    if v:IsA("Part") then
        print("Part found")
    elseif v:IsA("Model")
        b = v
        Tree(b)
    end
end

What happens there is the process stops when it hits the model rather than seeing what's inside.