"Honestly this is a win," another added. "Every year she needs to wear the hat!" a third insisted. "Nah but look how cute the baby is with it on," someone else grinned. "That sells it!" ...

Olivia Munn is celebrating a major milestone with her baby daughter ... turning 4 months old. In the adorable photo, Méi can be seen wearing a tan fuzzy trapper hat and is held up by her dad ...