my $FG_FrameInit = $PageFG -> LabFrame(                    -label=>"In
+itialize Device",
                                    -labelside=>"acrosstop",
                                    -borderwidth=>1,
                                    -relief=>"raised");

my $entry_FGDeviceAddress     = $FG_FrameInit -> LabEntry(        -lab
+el=>"Address:",
                                    -background=>"white",
                                    -width=>15,
                                    -text=>"ASRL7::INSTR",
                                    -labelPack=>[-side=>"left"]);
$balloon->attach($entry_FGDeviceAddress, -balloonmsg => "Device Addres
+s");

my $btn_FGInitDevice         = $FG_FrameInit -> Button(        -text=>
+"Init",
                                    -command=>\&InitFG);

    my @a = $FG_FrameInit->children();
    print "$_," for(@a);
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Tk::Frame=HASH(0x2228e0c),Tk::Label=HASH(0x221f384),
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You do not use a Frame, but a LabFrame, which is a Label + a Frame.

I gave the Frame as example. How can I get the children of some container (frame, labframe, toplevel...)