Larry Simms played the Bumsteads ' son in all the films ; his character was originally called Baby Dumpling , and later became Alexander .
Thus the Bumstead children grew from toddlers to young adults onscreen .
Larry Simms played the Bumstead ' son in all the films ; Bumstead 's character was originally called Baby Dumpling , and later became Alexander .
Thus the Bumstead children grew from toddlers to young adults onscreen .