Derma Parenting not working

[Dreamplay]

function closepagefunction()
if IsValid(mainmenufirstscreenframe) then
mainmenufirstscreenframe:Close()
end
end

function mainmenubackground()
mainmenubackgroundframe = vgui.Create("DFrame")
mainmenubackgroundframe:SetSize(ScrW(),ScrH())
mainmenubackgroundframe:SetPos(0,0)
mainmenubackgroundframe:SetVisible(true)
mainmenubackgroundframe:MakePopup()
mainmenubackgroundframe:SetDraggable(false)
mainmenubackgroundframe:ShowCloseButton(true)
mainmenubackgroundframe:SetTitle("")
mainmenubackgroundframe.Paint = function()
draw.RoundedBox(0,0,0,DM.FW:getWSize(mainmenubackgroundframe),DM.FW:getHSize(mainmenubackgroundframe),Color(100,100,100,255))
end
mainmenubackgroundframe:MoveToFront()
mainmenubackgroundframe:SetDrawOnTop(true)
mainmenubackgroundframe:SetMouseInputEnabled(true)
mainmenubackgroundframe.OnClose = function()
closepagefunction()
mainmenubackgroundframe:Remove()
end
end

function mainmenufirstscreenfunction()
mainmenufirstscreenframe = vgui.Create("DFrame",mainmenubackgroundframe)
mainmenufirstscreenframe:SetSize(ScrW()/3,ScrH()/4*3)
mainmenufirstscreenframe:SetPos(ScrW()/2-ScrW()/6,ScrH()/8)
mainmenufirstscreenframe:SetVisible(true)
mainmenufirstscreenframe:MakePopup()
mainmenufirstscreenframe:SetDraggable(false)
mainmenufirstscreenframe:ShowCloseButton(true)
mainmenufirstscreenframe:SetTitle("")
mainmenufirstscreenframe.Paint = function()
draw.RoundedBox(0,0,0,DM.FW:getWSize(mainmenufirstscreenframe),DM.FW:getHSize(mainmenufirstscreenframe),Color(255,100,100,255))
end
mainmenufirstscreenframe:MoveToFront()
mainmenufirstscreenframe:SetDrawOnTop(true)
mainmenufirstscreenframe:SetMouseInputEnabled(true)
mainmenufirstscreenframe.OnClose = function()
mainmenubuttonframe:Close()
mainmenufirstscreenframe:Remove()
end

mainmenubuttonframe = vgui.Create("DFrame" , mainmenufirstscreenframe)
mainmenubuttonframe:SetSize(DM.FW:getWSize(mainmenufirstscreenframe) - menumargin * 2,DM.FW:getHSize(mainmenufirstscreenframe) - menumargin * 2)
mainmenubuttonframe:SetPos(menumargin, menumargin)
mainmenubuttonframe:SetVisible(true)
mainmenubuttonframe:MakePopup()
mainmenubuttonframe:SetDraggable(false)
mainmenubuttonframe:ShowCloseButton(true)
mainmenubuttonframe:SetTitle("")
mainmenubuttonframe.Paint = function()
draw.RoundedBox(0,0,0,DM.FW:getWSize(mainmenubuttonframe),DM.FW:getHSize(mainmenubuttonframe),Color(100,255,100,255))
end
mainmenubuttonframe:MoveToFront()
mainmenubuttonframe:SetDrawOnTop(true)
mainmenubuttonframe:SetMouseInputEnabled(true)
end

concommand.Add("mainmenu", function()
mainmenubackground()
mainmenufirstscreenfunction()
end)
For some reason mainmenubuttonframe doesn't get parented to mainmenufirstscreenframe. Any ideas why?

[LegendarySoldier]

What does Panel/GetParent return?

[Dreamplay]

Prints the info GetParent would normally print. Weirdly enough works if i turn mainmenubuttonframe into a DButton