Select All Children Command
Use the Select All Children command from the Controls menu to deselect all currently selected controls and select all immediate children of the current form or control; for example, to move a block of controls to another parent, reposition a block of controls, or change properties on a group of controls.
This command is enabled only if the currently selected form or control has children.
If no control is selected, all immediate children of the form are selected.
2018.0.01 and higher