It means "my little" as in "my little one".
my boyfriend is called "mon petit ami" or "mon ami" in French
You can say "mon petit homme" in French to mean "my little man".
It means "my little rascal" in French.
French-masculine > "My Small (or little) Family"
"le petit-fils de mon père est mon (fils // neveu)" in French means 'the grandson of my father is my (son // nephew)' in French.
You would say "mon petit canard français" in French.
It translates to "I love my little vampire" in French.
ma petite maison means 'my little house' in French. "Maison" is a feminine noun so the possessive is 'ma' and not 'mon' which is used for masculine nouns. Same for the adjective.
Mon petit tresor
toujours dans mon propre petit monde means 'always in my own small word' in English.
mon petit chou EDITED: "Mon petit chou" translates to "My little cabbage". "Ou est mon petit chou" translates to "Where is my little cabbage". Or you can say "Ou est mon peu chou", which actually translates to "Where is my little cabbage". Petit = small Chou = little
mon petit ami