Managing Hierarchical Data - The Nested Set Model - insert node

Sorry for my bad english.
I want to add a child(Tom) to Chuck but not on the left of DONNA but on the right of FRED.
Can You help me ?

LOCK TABLE main_menu WRITE;
SELECT @myLeft := lft FROM main_menu
WHERE category_id = "Chuck";
UPDATE main_menu SET rgt = rgt + 2 WHERE rgt > @myLeft; UPDATE main_menu SET lft = lft + 2 WHERE lft > @myLeft; INSERT INTO main_menu(name_ita,name_eng, lft, rgt) VALUES('Tom','Tom', @myLeft + 1, @myLeft + 2);
UNLOCK TABLES;

            Albert (1, 12)
            /        \
          /            \
    Bert (2, 3)    Chuck (4, 11)
                   /    |   \
                 /      |     \
               /        |       \
             /          |         \
        Donna (5, 6) Eddie (7, 8) Fred (9, 10)